When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This is the most important post so far. It's a hell of lot easier to get to the engine compartment connections rather than the battery in the trunk.
That's how my BMW works.
Can any other "electrical" wizards out there chime in about the wiring just to confirm what ersatz reports??
Yep the wife's BMW X5 has and her prior Porsche Cayenne had clearly marked, easily accessed terminals in the engine compartment to connect jumpers.
If GM wanted those connections used they could have put a proper terminal at the fuse panel that was in the open with a cover that was easily removed and one for a ground.
PS: I find it's easy to get to the battery without ripping the carpet IF you first pull the bottom of plastic wheel well cover away by just disconnecting the bottom clips. Can actually remove those with your fingers. No need to remove the cover or the upper connections, just pull the bottom away. Unlike other clips used on the car these are are not very tight and can be easily pressed back. FWIW
You guys with coupes scare me! I can get to the battery in my convertible using my hands and it is very, very, very, easy to get the carpet out of the way and expose the battery. It takes 5 seconds to pull back the carpeting. It's actually a bigger nuisance to hold the carpet out of the way while you fool with the battery than it is to expose the battery.
^^^
Yep, there are posts where a dealer tech ripped their carpet! An AAA person would surly rip it! It's a raw edge and not bound. Depends on how tight the plastic wheel well cover fits the carpet. NBD to pull out at least the rear bottom clip, it's about 3 inches up from the carpet.
Clip is about 3 inches up from carpet. Can pull off with your fingers or use a screwdriver (or plastic trim tool if you have them) but a screwdriver tip would only be sliding on the carpet. Note the untrimmed carpet edge.
This is the most important post so far. It's a hell of lot easier to get to the engine compartment connections rather than the battery in the trunk.
That's how my BMW works.
Can any other "electrical" wizards out there chime in about the wiring just to confirm what ersatz reports??
The terminal is outside of the rear of the fuse box and right above the starter so the cable to the starter is short. Since starting the car is the primary need to jump the battery, the terminal is closer to the starter than the battery in the trunk.
Now, the issue is, getting the jumper clamp on the 12 volt terminal has to be done carefully. There are plenty of ground locations easily accessible on the frame under the alternator.
I use these terminals to connect my maintainer for winter storage because they are more accessible for the way my car sits on the lift and the electric supply. No cable running out of the trunk at the wrong end of the car.
For battery maintainer does it still keep battery charged when car haven't been driven for 2 weeks? I guess that's been too long maybe need to use it after 4, 5 days?
Any idea up to how many days that it will still keep battery charged when you haven't been using the car.
Details: Unlike past Vettes the C7 shuts everything down in ~10 minutes. Folks have reported starting the car when parked 30 days. I have gone on vacation several times for ~2 1/2 weeks when I had my September 2013 built 2014 C7. No problems starting. I have the equivalent of the GM charger but after the first month when I got the car, never used it! Below is a composite pic I made from info in the 2014 C7 GM Service Manual. Assumes when you drive the car it's more than 5 miles to a store so the battery is charged!
Bottom Line: With an 80% charged battery car should have ~50% charge left in 30 days, Enough to start car.
Jerry thanks a lot! Probably the same for Z06 right, since it shuts off everything after 10 min.
Thanks for taking the time to make that pic, pretty sure it will help a lot of people as it's pretty useful info!!
But battery maintainer I don't think it will charge the battery when it's at 50%....It just keeps it fully charged. Wonder within how many days of not using the car that you can still use the battery maintainer.
^^^
Thanks.
Yep, same with a Z06. The Maintainer will do fine charging the battery starting at 50% charge, that is still 12.2 volts. It won't charge a "Dead Battery" which would be a much lower voltage. It won't instantly charge it to 100% but in a day or two it would. It will charge at ~20% charge, ~12 volts, just will take longer. It will tell you when fully charged. It will also indicate when it can't.
Not using a charger, which I don't, assumes when you use the car you drive ~40 to 50 miles. The alternator does not instantly charge the battery either, although it puts out a lot more amps and can charge quickly-that doesn't mean a 5 mile trip to the store. In my street rod, 20 miles every two weeks was not enough to keep the battery charged! I seldom drive it now, mostly just goes to Shows, so it has a maintainer on all the time.
My car couldn't start after sitting for 2 weeks. I do have an OBD dongle I left plugged in. Otherwise it's got 4 years on the battery.
Jump started through the front bolt behind the fuse box and the alternator mounting bolt as a ground. Didn't have to turn on the donor car and left it connected only 10 seconds prior to starting.
Last edited by BrunoTheMellow; Mar 17, 2019 at 08:03 PM.
My car couldn't start after sitting for 2 weeks. I do have an OBD dongle I left plugged in. Otherwise it's got 4 years on the battery.
Jump started through the front bolt behind the fuse box and the alternator mounting bolt as a ground. Didn't have to turn on the donor car and left it connected only 10 seconds prior to starting.
But my dash is off...... ****.
FWIW, lots of discussion on the Forum in late 2013 re using that positive post to jump start. I looked at the size of the wire and it was 25% the size of what I used in my street rod that has it's battery in the far right rear- like the C7. I calculated the needed wire size. GM had some words in error in the 2014 Owner's Manual but only in the intro section. There was nothing in the section on jump staring about using that positive post. All reference to a location to jump start in The Owner's Manual was removed from all subsequent manuals.
I wouldn't use it but 10 seconds (if your saying the car started in 10 seconds) should not have caused overheating of the "too small wire."
FWIW, lots of discussion on the Forum in late 2013 re using that positive post to jump start. I looked at the size of the wire and it was 25% the size of what I used in my street rod that has it's battery in the far right rear- like the C7. I calculated the needed wire size. GM had some words in error in the 2014 Owner's Manual but only in the intro section. There was nothing in the section on jump staring about using that positive post. All reference to a location to jump start in The Owner's Manual was removed from all subsequent manuals.
I wouldn't use it but 10 seconds (if your saying the car started in 10 seconds) should not have caused overheating of the "too small wire."
I'd replace a 4 year old battery.
I edited my post. That problem was unrelated. I found a loose fuse from a previous project.
It worked just fine otherwise.
Last edited by BrunoTheMellow; Mar 17, 2019 at 08:27 PM.
Do not use the post on the fuse box in the engine bay to jump start your car. I believe it states that in the Owner's manual. The manual says jump start AT THE BATTERY terminals.
I edited my post. That problem was unrelated. I found a loose fuse from a previous project.
It worked just fine otherwise.
Originally Posted by eboggs_jkvl
Do not use the post on the fuse box in the engine bay to jump start your car. I believe it states that in the Owner's manual. The manual says jump start AT THE BATTERY terminals.
Elmer
Jump start only from the battery AND I'd still replace a 4 year old battery ESPEICALLY if it died.
Lead acid batteries are not like your cell phone! When dead it sulfated to some degree and may never be the same, especially and old one!
SIDE BAR Thought I'd look up the science:
Even though 80 percent of the capacity remains when a car battery dips to around 10.5 volts, the battery is considered to be fully discharged because taking the cycle any deeper will cause irreversible damage the plates through excessive sulfation.While normal sulfation is reversible, excessively draining a battery, or leaving it in a state of discharge, will allow the soft lead sulfate to crystallize. At that point, charging the battery will still cause some of the sulfation to reverse, but any crystallized lead sulfate will remain on the plates. This sulfate cannot, under normal circumstances, return to a solution in the electrolyte, which permanently reduces the available output of the battery.
The other detrimental effect of allowing crystallized lead sulfate to form is that it effectively shortens the lifespan of the battery in an empirically measurable way. If too much of this crystallization is allowed to occur, the battery will no longer be able to provide enough amperage to start the engine, and it will have to be replaced.
Once a car battery has been drained below a state of full discharge, the damage has been done. All you can do is check the electrolyte and put it on a trickle charger. If this is the first time that it has been discharged, you should be able to fully charge the battery and continue using it, but every time it is discharged below that threshold of 10.5 volts, the damage is done.
I have a Celtek 3300 that I use regularly and have it connected during my winter storage. I did read this on one of the descriptions of the 3300
I wonder if it will charge a completely dead?
CTEK Multi US 3300
56-158 CTEK Multi US 3300 Battery Charger. Compact and light weight, this battery charger does it all. Chargers all lead-acid batteries and includes a 4 step pulse maintenance charge to increase battery life and give superb performance. This little battery charge is so powerful that it will even charge completely dead batteries. Perfect for storing your Corvette. Add the cigarette plug adapter for easy one step use.
I have a Celtek 3300 that I use regularly and have it connected during my winter storage. I did read this on one of the descriptions of the 3300
I wonder if it will charge a completely dead?
CTEK Multi US 3300
56-158 CTEK Multi US 3300 Battery Charger. Compact and light weight, this battery charger does it all. Chargers all lead-acid batteries and includes a 4 step pulse maintenance charge to increase battery life and give superb performance. This little battery charge is so powerful that it will even charge completely dead batteries. Perfect for storing your Corvette. Add the cigarette plug adapter for easy one step use.
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '25
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
I was reading my 2014 Owner’s manual a couple of days ago and ran into the section on jump starting the car. I did see where it said there was a location under the hood for jumping the car. Nice to know that the manual is in error should the need ever arise.
I was reading my 2014 Owner’s manual a couple of days ago and ran into the section on jump starting the car. I did see where it said there was a location under the hood for jumping the car. Nice to know that the manual is in error should the need ever arise.
That was a carry over from the C6 manual and was corrected in the 2015 manuals. When they tossed the battery into the rear of the car for all C7s, they stopped with the front location to jump the battery.
Elmer
Last edited by eboggs_jkvl; Mar 18, 2019 at 10:27 AM.
Jump start only from the battery AND I'd still replace a 4 year old battery ESPEICALLY if it died.
