# I need an extension cord for my jumper cables!



## Chris616 (Dec 31, 2019)

Does the battery in your wife's car run down because of non-use?

I have fitted both of our cars (and some other equipment with electric start) with quick-connects for a battery charger, so when they aren’t being used enough to stop parasitic draw from discharging the battery they can be plugged in. The quick-connect means that nobody has to actually access the battery to make connections. And I do something to prevent the vehicle from being driven while connected.


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## Chris616 (Dec 31, 2019)

If access to your garage isn't uphill, convincing your wife to back into the garage would be one solution.


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## Steve2444 (Sep 28, 2020)

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Buy Schumacher SC1361 Fully Automatic Battery Charger, Maintainer, and Starter – 50 Amp/10 Amp, 12V - Car, SUV, and Small Trucks: Battery Chargers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases



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I have an old version of this unit.
It will start a car, or charge or maintain it.
I've only ever started a van with it once and it wasn't my vehicle.
But I have put it on batteries every so often to charge them and maintain them.

I haven't used jumper cables in decades, although I do have them.


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## Dodgewade (2 mo ago)

Chris616 said:


> Does the battery in your wife's car run down because of non-use?
> 
> I have fitted both of our cars (and some other equipment with electric start) with quick-connects for a battery charger, so when they aren’t being used enough to stop parasitic draw from discharging the battery they can be plugged in. The quick-connect means that nobody has to actually access the battery to make connections. And I do something to prevent the vehicle from being driven while connected.
> 
> View attachment 719509





gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...


I made me two or three sets that were about 20' long several years ago. I think my step daughter and step son have them. Before retiring I bought a set that was 20'. The ones I made were made from welding leads. The ones I bought are made of some good quality wire such as welding leads. If you make a set use the very good clamps. The cheap ones are just that -cheap and usually not worth throwing away much less bringing them home.


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## DoomsDave (Dec 6, 2018)

@gtomseeley I'd just get another set of cables and hook them together for the desired length.

I did that in my misspent yute' when I had more money for cables than batteries . . . . 

There are, of course, pitfalls to that, especially if the cables touch where they're hooked up (bbzzzzt!) but wrapping with a towel can help.

@Chris616 idea is a good one, but, if your wife balks, maybe just accept. My mom wasn't much for backing up cars, as she warned dad once and proceeded to demonstrate. 

In any case, let us know what you do. It will educate all of us.


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## Randy Bush (Dec 9, 2020)

Chris616 said:


> If access to your garage isn't uphill, convincing your wife to back into the garage would be one solution.


Op said can't get it out of park without battery power , so would not work.


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## Chris616 (Dec 31, 2019)

Randy Bush said:


> Op said can't get it out of park without battery power , so would not work.


I think that you misread my comment.


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## Randy Bush (Dec 9, 2020)

Oh ok would be closer for cables. LOL New battery might be a solution too.


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## Chris616 (Dec 31, 2019)

Randy Bush said:


> New battery might be a solution too.


Based on the OP's comment "As often as this crappy Ford battery craps out ", I'll guess that he's gone down that route a few times already.

I find that it's a lot less work to prevent the battery from draining that have to deal with the result. It also gives piece of mind. It's been a month since I drove my car, but that green light on the battery tender tells me that it'll start when I need it.


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## chandler48 (Jun 5, 2017)

Steve2444 said:


> I have an old version of this unit.


Steve, I used to have one of those, but found when using the "start" feature, if the car being started doesn't start, or you let off the starter, it has to reboot for about two minutes. 

@gtomseeley I'd invest in a good battery charger/starter. I found this one at a yard sale for very little money.


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## Steve2444 (Sep 28, 2020)

chandler48 said:


> Steve, I used to have one of those, but found when using the "start" feature, if the car being started doesn't start, or you let off the starter, it has to reboot for about two minutes.
> 
> @gtomseeley I'd invest in a good battery charger/starter. I found this one at a yard sale for very little money.


Didn't know that,


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## Domo (Nov 9, 2018)

You should typically carry jumper cables in both cars, anyway. If you did that you can take them both out and connect them in series for the extra length. Make sure the bare ends don't touch as you walk around.

Or, you can buy a gizmo that will probably stay in the garage - which will be of limited use when stuck in a parking lot.

I'd suggest stopping at Advance Auto or one of those places that will test your wife's car's battery and charging system - you can buy the second set of jumper cables while you're there.


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## SeniorSitizen (Sep 10, 2012)

Without any battery power, we can't even get her car out of Park and let it roll out of the garage into the driveway, which it would do.


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## rjniles (Feb 5, 2007)

30 foot 1/0 jumper cables $80









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## 660catman (Aug 25, 2019)

Get yourself a NOCO lithium boost pack. Portable and easy to use. No power cords to deal with when boosting. 


Retired guy from Southern Manitoba, Canada.


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## SPS-1 (Oct 21, 2008)

I have had problems (overcharging) when leaving a battery tender connected full time, but have used one many times to re-charge a battery that had run down due to lack of use. 
I leave it connected to the battery for 24 hours, and next day the battery is charged enough to start.

Finally, I got rid of the toys, and now just have one reliable Japanese car. No more dead batteries.


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## diyfunhere (4 mo ago)

gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...


no no no

get longer jumper cables


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## icerabbit (9 mo ago)

Options:
Battery charger with decent Amperage options + 12 gauge extension cord
Battery booster jump pack
New battery in the vehicle that has the seemingly weak battery and maybe some trickle charger for the future, if the vehicle gets used infrequently 

In periods of limited driving, I try to make sure our cars gets driven once a week, maybe two weeks; to top up the battery and roll the tires around. 

The only times I have had dead vehicle issues in recent years; was when there was an electrical short issue or that the computer systems do not shut down because there is door or trunk latch not closed or a malfunction with them, and the vehicle stays awake.


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## MTN REMODEL LLC (Sep 11, 2010)

icerabbit said:


> Options:
> Battery charger with decent Amperage options + 12 gauge extension cord
> Battery booster jump pack
> New battery in the vehicle that has the seemingly weak battery and maybe some trickle charger for the future, if the vehicle gets used infrequently
> ...


 I ike* RABBITS* options for you.

I can't imagine F'n with jumper cables all the time.

(Just a possible suggestion.... my Beemer 528XI had a known battery drain (all the electronics and alarms in it) and when just used for repeated short trips would drain bad. (And my wife used it for very short trips just down our street to friends,,, we were on a steep hill).

Battery was buried in the trunk... so for convenience I put some plug in pig tails on the battery that came out neatly in the trunk, and bought a $70 Schmacher charger/starter... you can power it off an extension chord if logistics requires.)


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## Missouri Bound (Apr 9, 2011)

Welding cables work fine.
You can get red and black cables from Amazon.....about $50 for two 25' cables.


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## wallmaxx (Dec 12, 2011)

Problem solved


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## FM3 (Aug 12, 2019)

gtomseeley said:


> What are some suggestions, please?


Stop letting the battery get that low. Every time it gets low, its life is shortened, and then you have to buy a new battery sooner.

The Motopower battery maintainers (slow chargers) have very good reviews and are around $20. Too bad you didn't post last week... Amazon had one of them on sale for $13.50. 

That's a maintainer/slow charger. If the car won't start, and you need it to start quickly, it will need more amps than the 1 or so the maintainers do. However, chargers with lots of amps may not necessarily work well either. I've put a 50 amp charger on cars that had their lights left on. Still didn't want to turn over. So used the 2 amp setting for 20-30 minutes, and then used the 50 amp. Started. Batteries prefer slow charging.

With so many battery problems, you might want to invest $20 or so in a battery load tester with LCD screen. Tells you the health and cranking amps of the battery like if you brought the battery to a shop or Autozone etc for them to test. But this way you can test it whenever you want.


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## CaptTom (Dec 31, 2017)

@wallmaxx has the answer. These new jump starters with the lithium batteries are great. They take up very little space and it's amazing how much power they pack. The one I bought already saved me once.

A few things to know: Look at the Amp rating. I got a 4000A model which is rated to be able to start the diesels in my boat. Having that extra oomph came in handy in my little commuter car when the alternator died on a remote stretch of highway. I only paid $130 for mine, and I see some on Amazon now for even less. You can get them with all kinds of extra features like flashlights, USB charging ports, even an air compressor. Figure out what you need, you don't need to spend $200.


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## Heathersdad (Jan 13, 2020)

Divorce the wife, sell the Ford Cmax, and buy urself an outboard Evinrude !


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## 660catman (Aug 25, 2019)

I’d dump the Cmax as Ford has discontinued them. 


Retired guy from Southern Manitoba, Canada.


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## lenaitch (Feb 10, 2014)

FM3 said:


> Batteries prefer slow charging.


Many years ago I was in a pinch. The distance was twice my jumper cables. I doubled-up the cables as one lead and found a length of old 300-ohm flat tv antenna cable to use as the other lead. I let connection run for about 20 minutes or so and the dead vehicle started right up.


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## Missouri Bound (Apr 9, 2011)

Don't spend your money on a charger if all you need are booster cables.







These are 30' and $40 at Amazon.


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## Mike Milam (Mar 3, 2017)

SPS-1 said:


> I have had problems (overcharging) when leaving a battery tender connected full time, but have used one many times to re-charge a battery that had run down due to lack of use.
> I leave it connected to the battery for 24 hours, and next day the battery is charged enough to start.
> 
> Finally, I got rid of the toys, and now just have one reliable Japanese car. No more dead batteries.


I've kept a Battery Tender on my 55 Chevy for 18 years and never had an issue. I use an Optima red top because I moved the battery to the trunk.


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## gtomseeley (Sep 2, 2019)

These are good answers! Thank you all. Ill try to reply here to a log of the ideas I’ve read.

imdidnt know I could daisy chain regular cables. Since a set for each car makes sense anyway, that might be best.

Ford has the car today for its 100k checkup. We’ve had ten years’ crappy experience with its electrical system, so “keep the battery from getting too low“ is a non-starter for us no matter how good an idea it is!

I’m glad to know 25’ cables are an option also. 

Wwe will wait till we hear what the Ford shop says about the car’s entire life expectancy from this point fwd. 

Thx again.


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## FM3 (Aug 12, 2019)

gtomseeley said:


> Ford has the car today for its 100k checkup. We’ve had ten years’ crappy experience with its electrical system, so “keep the battery from getting too low“ is a non-starter for us no matter how good an idea it is!


Well, especially in recent years of people driving less, or making short trips that aren't long enough to charge the battery, many suddenly realize they need to use a battery maintainer. And if the vehicle has a more serious electrical problem that drains the battery faster even when turned off, the maintainer will also counteract that.

Ford electrical problems or not, plugging in the car once a week or whenever sounds more practical than shortening the battery life and jumpstarting it and needing a second car to do it.


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## lenaitch (Feb 10, 2014)

FM3 said:


> Well, especially in recent years of people driving less, or making short trips that aren't long enough to charge the battery, many suddenly realize they need to use a battery maintainer. And if the vehicle has a more serious electrical problem that drains the battery faster even when turned off, the maintainer will also counteract that.
> 
> Ford electrical problems or not, plugging in the car once a week or whenever sounds more practical than shortening the battery life and jumpstarting it and needing a second car to do it.


Ya. The missus used have a Miata as her toy and would only drive it on absolute perfect days and only if the trip had a purpose (unlike me on my m/c, she never learned to 'just cruise' for its own sake). Anyway, I installed a maintainer harness on the battery so I could hook up one of the units I already had.


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## RonArt (Mar 6, 2020)

Back in the old days, when car bumpers were chrome, you could make common ground contact by having both cars' bumpers touch, then by clipping one end of one cable to the other, positive could be connected to positive on the other ends. 'hope you can use this.


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## ionized (Jun 8, 2012)

If the battery is dead after a reasonable length of time with no driving, something is wrong with the car, excessive parasitic load or a low output alternator. Motorcraft batteries have been shown to be good batteries by independent testers. Don't pay a premium price for a battery that is no better.

For a regulated charger it would be better to plug into a common extension cord of the proper gauge. Unless you way over-size the conductors on the DC end, the charger will regulate better since it sees the battery voltage at the end of the cable it is designed for, not the additional voltage drop. In addition to that, 120 VAC means less current and you need a lot less copper to carry it. An extension cord is going to cost a lot less than welding cable of the same length.


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## Tom153 (Nov 10, 2016)

gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...


Battery charger that plugs into 120V. Use an extension cord if no nearby outdoor receptacle.


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## schaan (8 mo ago)

gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...


 another pair of jumper cables clipped to one end of the other ones works great I got a little battery power bank that works pretty well.


gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...





Google Image Result for https://preview.redd.it/cp5wwgbeugq11.jpg?auto=webp&s=3eb4e4da101aab60fb93ee017c32691eb8e38d9d


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## schaan (8 mo ago)

schaan said:


> another pair of jumper cables clipped to one end of the other ones works great I got a little battery power bank that works pretty well.
> 
> 
> 
> Google Image Result for https://preview.redd.it/cp5wwgbeugq11.jpg?auto=webp&s=3eb4e4da101aab60fb93ee017c32691eb8e38d9d


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## Darkkhelmet (May 22, 2018)

gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...


If you don't want to get a battery tender (though I recommend you do) for the car you might want to consider a small booster battery. I got one at COSTCO for around $40 and have used it a few times. It's wonderful when you come across a weak or dead battery. They're small and light and handy to have around. You should also try and determine why the car battery is dying. The battery should hold enough power for weeks or months and be able to start a car.

As for garage space, I have a full size SUV and a 900 pound touring motorcycle in my one car garage. If I gain any more weight I will not be able to get out of the car when I park it inside the garage. Basements and sheds are for "stuff"  IMO.


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## waltermitty (Mar 24, 2014)

I didn't realize until a year ago that many of the tiny, portable booster packs utilized super capacitors which function like heart defibrillators. It uses the remaining voltage in the car battery and amplifies it enough to jump start the car. However, if the car battery is very weak, it may not be enough to energize the capacitor sufficiently.

What gets hidden in the advertising of those Noco et al units is the size (micro/farads) of the capacitor. That, along with the size of the lithium battery, are key components in the booster's engine. The booster pack's lithium battery serves to supply volts to the capacitor that the car battery may be lacking.

For want of an attractive size and portability, the booster's battery and capacitor are kept relatively small. It is rare that the technical specs reveal the true details of what is assembled in the booster pack. Ergo, the Youtube videos are full of rough and subjective reviews.

blah blah....all that just to say that I did buy a Topdon jump/boost pack (like the Noco) since it was marketed at heavy discount by Amazon and with decent reviews. True to hacker DNA, the first thing I did was disassemble it to look inside. Not satisfied and wanting more reserve power/capability, I proceeded to assemble one for kicks. It is about 7 lbs and the size of a 6-pack yet is still light enough to grab toss into the truck to help bail out a family member or colleague. It's quite satisfying to connect and wait for a few minutes and then yell "CLEAR!" and listen to the vehicle roar to life


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## jagman653 (5 mo ago)

Get rid of the junk, or at least half of it. Why keep junk in the garage while leaving your valuable car exposed to the elements.
Forget the long battery battery cables. You can just move your charger and use an extension cable.

Rather than moving my charger, I prefer keeping it on a small shelf mounted on the garage wall near the charger/boost posts. After contacting Schumacher tech support I bought about 10 feet of AWG 14 2-conductor cord fitted with ordinary charger clamps. Took the case off the charger and fitted my new extra long cables. I wanted to post photos of my setup but couldn't figure out how to embed photos in a post🤔

BTW, check your car's service manual or owners manual regarding the proper way to connect a charger or boost start device. *Hint:* It's almost certainly *not directly to battery posts* while the battery is in the car & connected. Otherwise, the *cars electronics can be damaged.*


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## Scrutator (Aug 24, 2021)

FYI: Five years ago or so I bought the best jumper cables I've ever had. They're incredibly flexible with high-quality clamps. They are available up to 25 feet long. I purchased them for both of my vehicles. They're pricy but worth it in my opinion. Quality Jumper Cables


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## chandler48 (Jun 5, 2017)

To post a picture, look at the tray at the bottom. Click on the paper clip and link to your picture. Just for information, 14 gauge wire won't boost a car. It may allow for trickle charging, but not boosting


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## jayhanig (Feb 1, 2019)

gtomseeley said:


> Are extra long battery cables even an option? Would just owning a spare car battery work? Is it worth buying one of those portable charger kits? As often as this crappy Ford battery craps out, maybe that's the best choice! But I'd like opinions from the experts first.
> 
> Thx.


You need three different things:

1. I have a battery maintainer on every key operated vehicle I own: a car, truck, boat, and motorcycle. The maintainers are capable of desulfinating the plates of a battery and they're smart enough to stop charging when the battery is fully charged. I use the ring terminal connectors that are just long enough to reach outside the hood so it doesn't have to be raised to make the connection. All of the maintainers stay inside the garage and if the output cord isn't long enough, I just add a 25' extension to it. (The extension is made for 12 volts and it doesn't matter if it gets wet or not.) This is for normal maintenance and should be used every time you park for the last time of the day. My vehicles are on their maintainer any time I'm not actually driving it. I get a good two years of extra life out of batteries using the maintainers compared to not using one. A 1.5 amp maintainer can be had for about $25.

2. You need at the very least a higher amperage 12-volt charger, preferably one that has a starter capability. This is for the situation you found yourself in when you wrote your query. This charger can be taken outside if need be, but it can't be left out in the rain. You would extend its range by using a heavy duty outside extension cord, meant for 120 volts, and would set it on top of the vehicle's radiator while it's doing its thing. You can find one of these capable of putting out 50 amps for starting a car for about $75.

3. Finally, you need a set of jumpers in each vehicle. This is for when you come out of the grocery store and it won't start. Going up to strangers and asking if they have jumper cables is a sketchy thing and probably doomed to failure. It's a lot more difficult for a stranger to refuse you when you're holding a set of jumpers in your hand. What are they going to use as an excuse to turn you down? That they walked? I don't think so. Make it easy for others to do the right thing, and they probably will. This won't cost you anything since you already have 2 sets, right?


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## Langer1 (Aug 24, 2021)

rjniles said:


> 30 foot 1/0 jumper cables $80
> 
> 
> 
> ...


Cheap cables like that are aluminum and don't hold up.


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## WestofYoulb (May 22, 2020)

gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...





gtomseeley said:


> I'm not joking. We own 2 small cars and we have a double garage. But we all know garages aren't for cars, they're for "stuff". So we never park both cars inside. It's almost impossible, with all the "stuff", to even do that! So my wife always parks her Ford Cmax right in the middle of the open space and I leave my little two-seater Honda CRZ outside.
> 
> But when, like today, her battery dies, we can't get both cars in the garage at once and my typical battery cables won't reach even when I get my car as close to the garage as I can.
> 
> ...


Here is what we used to do. Park the cars end to end and touching metal bumpers. Voila! A negative connection, so join the two cables end to end and attach to both positives. Now youare fully connected.
Alas, no metal bumpers any more, but if you can get the cars touching, say, door handles or wheel hubs, it would work.
But why would this come up more than once a year? Why is one car running its battery down constantly?
Anyway, why not just buy a second set and join them together?


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## FM3 (Aug 12, 2019)

jagman653 said:


> I wanted to post photos of my setup but couldn't figure out how to embed photos in a post🤔


Drag and drop the file into the reply area.


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## ionized (Jun 8, 2012)

WestofYoulb said:


> Here is what we used to do. Park the cars end to end and touching metal bumpers. Voila! A negative connection, so join the two cables end to end and attach to both positives. Now youare fully connected.
> Alas, no metal bumpers any more, but if you can get the cars touching, say, door handles or wheel hubs, it would work.
> But why would this come up more than once a year? Why is one car running its battery down constantly?
> Anyway, why not just buy a second set and join them together?


I'd worry about this a little. if you are not careful, you could end up running many amps through a relatively small ground strap and turning it into smoke.


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## FM3 (Aug 12, 2019)

ionized said:


> If the battery is dead after a reasonable length of time with no driving, something is wrong with the car, excessive parasitic load or a low output alternator.


It would be interesting to hear what potential electrical fault the dealer may find with the car since if the battery is dead while in the garage, and then they jump it and drive off and never use a wall charger on it, that means the car's alternator must be plenty strong since it's charging up a battery so dead it needed jumpstarting but then apparently the car works fine for a while.


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## ionized (Jun 8, 2012)

FM3 said:


> It would be interesting to hear what potential electrical fault the dealer may find with the car since if the battery is dead while in the garage, and then they jump it and drive off and never use a wall charger on it, that means the car's alternator must be plenty strong since it's charging up a battery so dead it needed jumpstarting but then apparently the car works fine for a while.


You can have a chronically poor charging system and drive the car for a very long time without noticing anything. If the starter and its connections are very good (cables in good shape and connections solid and no oxidation), it can push through. The first indication of poor charging might be a battery that fails prematurely because it sulfates. Normally you park it at full charge or nearly so. If you constantly bring it to, maybe, 1/2 or 3/4 charge, the battery ages fast. That's why good practice is to check the charging whenever a battery is replaced.

Here is another factor to consider with respect to the charging. Cars end up with parts off the shelf that best match each other, but not perfectly match each other. Auto manufacturers are not going to have unique alternators, starters and batteries specified, built, and stocked for each of their models. (Figure in the cost of stocking all the replacement parts too!) You can end up with a relatively oversized battery, alternator or starter, or maybe not. If this particular model got a relatively small alternator and a big battery and it has excessive parasitic load, it could push it into the sulfating range more frequently than another model. 

As an example of parts commonality between very different engines/models, I recently made the observation that my wife's 4 cyl Ford uses the same AC clutch as my 4.6l V8 Merc. Note that both of these cars are old enough to buy adult beverages in any state. (I did not actually try to figure out if the same compressor is used.) I noticed because the Ford got a new compressor recently and , right after that, Merc needed a new clutch. There was a delay in my getting the clutch in and I realized that I could swap over the clutch that was still sitting on the garage floor on its old compressor. The Merc was not drivable with the clutch pretty blown up. In the end, we arranged it so we only needed one car for a day and I decided that it was not worth the time to put the used clutch on even though it did not look like it had much wear.


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## FM3 (Aug 12, 2019)

ionized said:


> You can have a chronically poor charging system and drive the car for a very long time without noticing anything.


Correct, but this thread is different. OP is jumping a dead battery and then driving away, and then the car is fine for x amount of time until it needs a jump again. If OP's car has a poor charging system, it wouldn't be recharging the battery enough to last x amount of time after being dead.


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## ionized (Jun 8, 2012)

How long it is before the battery fails to start again depends on the magnitude of x and some other variables, including the length of the drives, time between the drives, the charge rate of the alternator, the condition of the battery, the use of accessories and any parasitic (normal or excessive) load.


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## Head_Unit (Jan 26, 2010)

gtomseeley said:


> We’ve had ten years’ crappy experience with its electrical system,


With the whole electrical system? = change vehicles already for heavens sake. Or is it just the battery? I see this thread is about a month old but I'm still curious:
???You've changed the battery multiple times or if this is the same battery dying over and over???

I worked as an automotive test engineer, once a battery dies a couple of times it is trash, especially in cold climates.
A battery not driven on long trips regularly, or in a vehicle with a discharge problem, or a weak alternator, needs a trickle charger connected. Period. I've used several each of these with no problems of overcharging or whatever https://smile.amazon.com/gp/product/B07H97P93H and https://smile.amazon.com/gp/product/B000CITK8S
Car off, unplug the battery terminal, connect a DC ammeter between the now-loose terminal and the battery post. How much current is draining?


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