so question...

little calmer now - but... took my car to an electrical mechanic today... (watched and learned a little bit, I haven't worked much on cars for the electrical portion of things)...

a) trickle charged my car for 2 days, battery reading was about 11.5V, when I drove, charged, then when I turned car off, battery was about 12.1V
b) he took a voltmeter just running, about 14V
c) applied a load (raised headlights, moved windshield wipers), still seemed to charge okay (I forget, I think it was slightly less voltage, but still a 'charging' voltage)
said battery seemed okay (I think he measured afterwards and said since it was at about 12.6V that meant the battery was '80% good')
d) I think he read the codes, cleared them, stopped/started the car then got the 1214 error (ABS/traction control/etc module).

So going to get that fixed (he'll take it apart, resolder the insides, etc., I guess basically what the absfixer.com site does).

Figured car was okay to drive, drove about 5 minutes, everything good. Stopped, turned car off (but key in ignition) because I was putting the top up, did up passenger window,
then all of the sudden abs/traction/etc light goes on, and I noticed the driver side window didn't work.

While driving home, the gages went totally wonky again, had some voltage fluctuations (had the DIC gages to read the charging rate), was fairly steady about 13.4 V, then went about 13.1V for 1/2 second,
then back to about 13.4V... concerned, but got it back up, plugged it back into the trickle charger...

phoned him back (see if I can get an ealier appt, today was just an inspection)... told him what happened, he said maybe there is something with the charging system as well, that he'll test after he gets the abs module fixed...

my questions are this:
a) does it sound like a charging system issue as well - or - even though the battery "seemed" good - could there still be something wrong with the battery? (reading other threads people have suggested replacing the battery - should I *still* do that regardless, even though it 'seems' when he tested it things were fine?) (Basically - I'm wondering if I should still replace the battery *regardless* of what the electrical mechanics tests show, which was just the simple volt reading/test)
b) one thing I was really concerned about when the gages went wonky was the coolant temp - is the coolant still regulated properly (lo/hi fans going on at 108C/113C) even when the gages went wonky (and coolant gage was all the way to the right?) since I couldn't see the coolant temp, was worried what if the fans didn't work/etc - but not sure if that is a separate system...

thanks for the help!

 

https://www.corvetteforum.com/forums...ease-help.html

Do you need to start a third thread in two days? We can keep the conversation in one thread.

12.1V indicates a DEAD battery. Not fully dead, but mostly dead. It did NOT "seem" good. You may think that since everyone refers to the 12V system that 12.1V is healthy but it is not. A healthy fully charged battery is going to show in the 12.5 - 12.9 volt range, depending on battery type.

Please get a new battery.

The thermostat is purely mechanical.

The electrical fan control is not guaranteed to work properly if your electrical system is behaving funny. Get a new battery.

 

read up on cleaning the grounds and dont worry about the abs just yet. Fix the other problems first. get a new battery first

 

 

12.1 indicates a dead batt ????????????????? my car has started numerous time at 11.6 or lower ??? I still would suspect the batt !!!!

 

Aren’t there several threads about this issue already? You should keep it all in one thread. Hard to keep track of advice at this rate.

 

cleaning up what grounds? (I am not sure what this is in reference too?) - already scheduled an appt for the abs - but you think just replacing the battery (& whatever you mean by grounds) might fix that?

thanks!

 

Do a search re grounds from bill Curlee in the stickies.

 

these are the ground locations !!

 

This picture is in Pounder's post above (last page), but this may make it a bit easier to correlate to actual locations on the chassis.


Good luck... GUSTO

 

A "fully charged" battery showing 12.1 volts does, in fact, suggest the battery is on death's door if it hasn't crossed it yet.

You can start an engine with a lower voltage, sure. Doesn't mean it's a happy healthy battery. Many C5s have notoriously flaky electronics, as you know, that really demand a voltage within a range that allows less 'slack' on the low end.

 

Just an advice, you should keep this in 1 thread. Having multiple threads at the same time with the same problem will only create confusion.

How are you taking the readings I highlighted above? To be able to determine if your charging system and battery are working properly, readings have to be taken directly at the battery posts with a multimeter.

You should take your battery out of your car, fully charge it and then take it to an auto parts store to be load-tested. Otherwise you are going to continue guessing.


What you mentioned regarding your window not working and all your gauges going crazy simultaneously seems to point to corruption in the Serial Data Bus. I would suggest to put on hold the BCM project until you clear this out first, as well as the battery issue. Click here for details on how to proceed.

 

it's Amps that starts the car NOT volts !!!!!!!!!

 

Yes, Pounder, amps start the car, but the voltage a car battery is capable of keeping tells you the health of the cells.

Every single commercially-produced battery chemistry is fairly well understood. There are many ways of testing the health and charge level of a battery. Lead-acid batteries, including AGM, can have their charge level / health approximated by the following chart.

Do note that if you have fully charged a battery to the point where your charger/floater has decided that it can no longer charge higher, but only shows ~50% capacity, that means your battery needs replacement.

 

so what your telling me is my car should NEVER start showing 11.6 ????

how I always know what my voltage is !!!

 

If your neat little voltemeter is showing 11.6 volts, check it with a proper multimeter.

 

I don't need to, I know it's right on !!!!!!!!!! also know a batt showing 12.1 is NOT dead !!!!!!!

 

This is wrong. In a DC motor Torque is proportional to Current and Speed is proportional to Voltage. Both of them need to be above certain thresholds so the starter can overcome the engine mechanical resistance to be cranked AND to do so at an appropriate speed so it can start.

 

so when you buy a batt, why is the most important thing to look at is "cold cranking amps" ??????

 

I have worked on so many vehicles in my life, and for a long time diesel cars, I definitely know what will start a car or not !!!!