Need help diagnosing weird electrical problem
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Joined: Dec 2007
Posts: 101
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Need help diagnosing weird electrical problem
1. Noticed car cranking a little slower than usual - started thinking about checking battery/alt.
2. One week later, noticed that doors did not open easily - took several squeezes to get action - time to check battery! (car still cranked OK, but a little slower)
3. Batt volts 12.3 (low) Alt 14+ (OK) Drove 20 minutes - Batt 12.6v and doors worked fine.
4. Next AM - doors difficult again - bat 12.3 - car still cranked OK.
5. Changed battery in key fob. Doors still quirky next AM.
6. Took car to Advance to test "Gold" battery - 18 months old, still under free replacement warranty.
7. Tested as "OK, but needs charging".
8. Returned home - took batt out of car - charged battery - took less than 1 hr at 10A - fully charged to 13V.
9. Reinstalled - all good for 1 day - now neither doors nor hatch will open with fob.
10. a. Battery still shows 12.5v.
b. Opened doors with key/latch pull - car started OK.
c. Idled car for 10 minutes - shut down - batt shows 12.6 - all doors and hatches open automatically again.
11. I am sure that when I try again tomorrow, they will not!
Anyone seen anything like this? Does not make sense that door and hatch latches would require more power than the starter!
2. One week later, noticed that doors did not open easily - took several squeezes to get action - time to check battery! (car still cranked OK, but a little slower)
3. Batt volts 12.3 (low) Alt 14+ (OK) Drove 20 minutes - Batt 12.6v and doors worked fine.
4. Next AM - doors difficult again - bat 12.3 - car still cranked OK.
5. Changed battery in key fob. Doors still quirky next AM.
6. Took car to Advance to test "Gold" battery - 18 months old, still under free replacement warranty.
7. Tested as "OK, but needs charging".
8. Returned home - took batt out of car - charged battery - took less than 1 hr at 10A - fully charged to 13V.
9. Reinstalled - all good for 1 day - now neither doors nor hatch will open with fob.
10. a. Battery still shows 12.5v.
b. Opened doors with key/latch pull - car started OK.
c. Idled car for 10 minutes - shut down - batt shows 12.6 - all doors and hatches open automatically again.
11. I am sure that when I try again tomorrow, they will not!
Anyone seen anything like this? Does not make sense that door and hatch latches would require more power than the starter!
Le Mans Master
Joined: Jun 2008
Posts: 8,255
Likes: 411
From: Mt. Sinai NY
Your car needs a new battery. All of these symptoms are classic signs of a defective battery. Even if it tests good....even if you charged it.....one or more of the cells in your present battery is not functioning
Clif
Clif
Melting Slicks
Joined: Dec 2013
Posts: 2,232
Likes: 315
From: Bridgewater New Jersey
I would take it to another shop or unrelated brand parts store and have a good load test on the battery. As others here have said, sounds like it's giving up, and also sounds like your charging system is working OK, since you were able to get a charge by driving for a while.
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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I agree that you need a new battery. When your your car is not in use you should keep it on a good battery tender, like a C-Tek 3300. Newer Vettes (C6 and C7) are battery eaters. When not in use the battery is maintaining many systems.
Last edited by capevettes; Nov 22, 2018 at 05:04 AM.
Safety Car
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Melting Slicks
Joined: Oct 2013
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From: Central Ohio
I think the real fix will be a two or three fold solution
i would start with a new battery and check the electrical connections at/on the starter.
the starter electrical connections are key to feeding the rest of the car, they are known for coming loose, corroding and or breaking.
So I would replace the battery and check the starter electrical adjust and replace as needed first.
any additional glitch’s I would replace the alternator.
not sure why but the c6 is quite fussy about batteries
i would start with a new battery and check the electrical connections at/on the starter.
the starter electrical connections are key to feeding the rest of the car, they are known for coming loose, corroding and or breaking.
So I would replace the battery and check the starter electrical adjust and replace as needed first.
any additional glitch’s I would replace the alternator.
not sure why but the c6 is quite fussy about batteries
Last edited by 1968swbbigblock; Nov 22, 2018 at 09:23 AM.
Pro
Joined: Jun 2003
Posts: 575
Likes: 35
From: Sandy Springs GA
Back in my C6 days, Before you purchase a new battery First Check the main wires to battery and the main wires to the starter and alternator. I had a similar problem. I found the positive connection from the battery to the starter was barely connected at the starter. The cable was damaged due to heat from the cats system. I tighten the connection, added a heat shield to the starter, all is good
Last edited by Reggied; Nov 22, 2018 at 01:41 PM. Reason: added more stuff
Le Mans Master
Joined: Jan 2008
Posts: 6,457
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From: corpus christi Texas
What year?....Anyway I would replace your door pads also.I never have over 12 volts after sitting overnight,It stays around 11.8 but doors open fine and it fires right up and my alternator shows 14.7 then drops to around 14.3 after a few minutes...Brand new AC Delco battery....Good Luck
Burning Brakes
Joined: Oct 2015
Posts: 820
Likes: 332
From: Orlando Florida
It sounds like two different problems. First being your cars battery may be low and needing replacement, the other is accessing your car with the key fob. The key fob does not open the doors, it unlocks them. Is your problem just unlocking the doors and opening the hatch? Or, after you unlock the doors are you also having problems opening the doors with the touch pad on the door?
Le Mans Master
Joined: Jan 2008
Posts: 6,457
Likes: 297
From: corpus christi Texas