C5 corvette electronics going crazy... And won't start
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Low voltage can cause a relay to buzz as it tries to do it's job. It can cause the relay to fry itself to death. You could have affected one or two like the TDR that will cause the car to not start. Need to identify which relays are doing this and tell us.
Have you checked your connections at the starter? Loose, bad wire crimps, etc.
If you want I can provide guidance on how to jumper around the TDR circuit to crank the car and see if it will run.
Have you checked your connections at the starter? Loose, bad wire crimps, etc.
If you want I can provide guidance on how to jumper around the TDR circuit to crank the car and see if it will run.
Thread Starter
Safety Car
Joined: Jun 2014
Posts: 4,637
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From: WDE
St. Jude Donor '14-'15
Ok so I charged it all night. I let it sit for about 10 minutes, then hooked it back up to the charger, and it said it was still charging, so I questioned that.
I then went and got my volt meter, and as soon as I unhooked it from the charger it was reading 12.05 and quickly fell back down to 11.95. Not sure if that is a big deal or not. I've yet to hook it up to my car yet
I then went and got my volt meter, and as soon as I unhooked it from the charger it was reading 12.05 and quickly fell back down to 11.95. Not sure if that is a big deal or not. I've yet to hook it up to my car yet
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
Ok so I charged it all night. I let it sit for about 10 minutes, then hooked it back up to the charger, and it said it was still charging, so I questioned that.
I then went and got my volt meter, and as soon as I unhooked it from the charger it was reading 12.05 and quickly fell back down to 11.95. Not sure if that is a big deal or not. I've yet to hook it up to my car yet
I then went and got my volt meter, and as soon as I unhooked it from the charger it was reading 12.05 and quickly fell back down to 11.95. Not sure if that is a big deal or not. I've yet to hook it up to my car yet
Thread Starter
Safety Car
Joined: Jun 2014
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From: WDE
St. Jude Donor '14-'15
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
Thread Starter
Safety Car
Joined: Jun 2014
Posts: 4,637
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From: WDE
St. Jude Donor '14-'15
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
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Le Mans Master
Joined: Sep 2013
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From: Wisconsin
Thread Starter
Safety Car
Joined: Jun 2014
Posts: 4,637
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From: WDE
St. Jude Donor '14-'15
Ok. Car started.
As soon as I cranked it battery voltage on the dash was 10.5. Quickly dropped to 9.7 with the red light saying check gauges and low voltage message.
I then checked voltage on the back of the alternator... It was 3.224-3.300.
As soon as I cranked it battery voltage on the dash was 10.5. Quickly dropped to 9.7 with the red light saying check gauges and low voltage message.
I then checked voltage on the back of the alternator... It was 3.224-3.300.
Thread Starter
Safety Car
Joined: Jun 2014
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From: WDE
St. Jude Donor '14-'15
Melting Slicks
Joined: Jul 2002
Posts: 2,223
Likes: 556
From: Tallahassee fl
they are ultra voltage sensitive. I had my battery tested at multiple places and one said it was clearly bad and the other two said it was just undercharged. The 2 were wrong (for a C5). What a normal car can take for voltage variations the C5 can't. A battery that is 80 percent good will work fine on most cars but won't on ours.
I keep mine on a trickle charger. Another tip if is if it sits for more than a couple days.... turn on the key and let everything fully cycle. after all the noises stop crank the car. It starts better like that after sitting.
I keep mine on a trickle charger. Another tip if is if it sits for more than a couple days.... turn on the key and let everything fully cycle. after all the noises stop crank the car. It starts better like that after sitting.
Thread Starter
Safety Car
Joined: Jun 2014
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From: WDE
St. Jude Donor '14-'15
Now I have battery back on trickle charger. Trying to figure out my next move. I know a lot of people have issues buying alternators. Not sure If I should get this one rebuilt... Or if that's even the issue. I've already replace the voltage regulator and brushes in it this week..
Le Mans Master
Joined: Jan 2004
Posts: 9,488
Likes: 1,743
From: Knoxville Tn
Did the car start and run after you trickle charged it over night?
Did the electronics look normal if it did start?
If it were me, I'd take a hour drive with the lights on, then shut it off and try to start it. If it starts, let the car set over night and see what happens in the morning.
Did the electronics look normal if it did start?
If it were me, I'd take a hour drive with the lights on, then shut it off and try to start it. If it starts, let the car set over night and see what happens in the morning.
Thread Starter
Safety Car
Joined: Jun 2014
Posts: 4,637
Likes: 0
From: WDE
St. Jude Donor '14-'15
Did the car start and run after you trickle charged it over night?
Did the electronics look normal if it did start?
If it were me, I'd take a hour drive with the lights on, then shut it off and try to start it. If it starts, let the car set over night and see what happens in the morning.
Did the electronics look normal if it did start?
If it were me, I'd take a hour drive with the lights on, then shut it off and try to start it. If it starts, let the car set over night and see what happens in the morning.
Electronics and everything finally looked normal.
Car was running at about 9.7volts (said on dash ) before I cut it off. I don't think I'd make it very far if I tried to drive it like this
Pro
Joined: Jul 2010
Posts: 590
Likes: 57
From: Aurora Colorado
Have the battery load tested. After fully charging battery--- if below 12.6 volts with nothing connected to it-the battery is bad.
You said in an earlier post that your old battery was below 12 volts disconnected and just charged. No way in the world is that battery good.
A good battery, just charged and without being connected ,should have a surface charge of more than 12.6 volts.
Replace battery. Buy a new AGM battery with at least 700CCA rating with at least 120 minutes RC . And then charge the new battery for 24 hours before installing in the Corvette.
You said in an earlier post that your old battery was below 12 volts disconnected and just charged. No way in the world is that battery good.
A good battery, just charged and without being connected ,should have a surface charge of more than 12.6 volts.
Replace battery. Buy a new AGM battery with at least 700CCA rating with at least 120 minutes RC . And then charge the new battery for 24 hours before installing in the Corvette.
Last edited by phoneman91; Jan 26, 2015 at 01:23 AM.
Safety Car
Joined: Dec 2010
Posts: 4,820
Likes: 34
From: Ravensdale WA
Go AGM. Your ECM is below the battery and AGMs wont leak. If you have a bad alternator that could have ruined your battery. Quit messing around with a bad alternator and get a good one from NAPA. Stay away from Auto Zone and Orlieys.They sell garbage rebuilt parts. However you need to check the wiring first. The power at the batt term on the alternator should be the same as the battery. There may be no connection between the two.