IMPORTANT ELECTRICAL INFORMATION (Long!)
I just read your post on electrical information on your corvette. I own a 2003 corvette and I am having electrical issues that I can't seem to get someone to fix. Here is what happens to my car. I will be driving along and all of a sudden my gauges stop working, my radio and AC goes off, bells starts sounding and all the messages that could possibly displayed are displayed. However, the car still runs good. A little later it will pop back on again! If I turn off the engine and restart it, it will be ok. I might drive for another 6 hours before it happens again.
It is now at a Chevy dealer and they had the car going on the 3rd day and can't find anything wrong with it. I am going to print off your post and take it to them this morning and hope it will help them. They also contacted a support group at GM. They said there was a bulletin put on saying something could be wrong with the wiring under the seats. They checked it out and all was fine..
It sounds like from your post that your issue was just the error messages being generated..?? Mine the whole computer stops working....
Thanks for your post! I hope that it will help me out!
Bob






http://forums.corvetteforum.com/c5-g...lem-found.html
I just read your post on electrical information on your corvette. I own a 2003 corvette and I am having electrical issues that I can't seem to get someone to fix. Here is what happens to my car. I will be driving along and all of a sudden my gauges stop working, my radio and AC goes off, bells starts sounding and all the messages that could possibly displayed are displayed. However, the car still runs good. A little later it will pop back on again! If I turn off the engine and restart it, it will be ok. I might drive for another 6 hours before it happens again.
It is now at a Chevy dealer and they had the car going on the 3rd day and can't find anything wrong with it.
There were actually 3 things I did and the problem is gone. First. I changed the ignition switch. My key would almost come out driving down the road anyway. That cleared the security light on the dash. I cleaned all the chassis grounds I could get to. (did accordian door tubes too) The main culprit for me was the wiring harness under the drivers seat. It was damaged. After I repaired the harness all the problems went away.
Hope this helps a little.
Rick
Last edited by Rick Perkins; May 22, 2009 at 07:48 AM. Reason: added info.
Any ideas?
I want to let everyone know how great Bill was in pinpointing an electrical problem I was having. I had my car to two places telling them of my electrical problem and neither one of them could find the problem. The problem I was having is when driving my car the computer would just quit working. All my gages would go crazy and tons of error messages. I saw Bills post and he got a hold of me and said look at the wires between the doors and the body. You will find a clear wire there. Tape it up and it should fix the problem.
I then drove my car home from the dealer and did just that. At the time I thought I would never find out what is wrong with my car. I looked at the wiring and sure enough, there was a clear wire and right where it goes into the connection and where it comes out of the connection there was about a quarter of an inch of BARE wire showing. I taped it up and I have not had an issue yet. I think the problem is solved!!
Thanks Bill for everything!!!!
Bob from St. Louis
When I had my car in with the same problem you were having, the dealership call GM and was told that there was a bulletin put out on a problem with the wiring under the seat. For me they couldn't find anything wrong.
You can see my post where Bill ID the problem. It was the wiring between the doors. I had a bare wire about a quarter of an inch going in and out of the connector. Taped it and all is fine.
Thanks for replying.
Bob
The Best of Corvette for Corvette Enthusiasts
My car was in the shop for two month, getting a lot up updates. I had a new RSI Dual pump installed in the left tank, with a brand new fuel level sensor installed. I did verify it was readinf 40 ohms at one end, and 200+ Ohm on the other end (I dont remember exactly what the top was). Well, the gas gauge shows empty! The shop put 5 gallons in it, and it did not move. They took it to a gas station and filled it up, still showing empty. They ran through all the diagnostics that is in AllData, and now they think the PCM is bad, and wants to replace that.
My question is, how can the PCM just go bad? The gas gage was working when I brough it to them.
Has anyone else experienced this kind of issue?





BC





My car was in the shop for two month, getting a lot up updates. I had a new RSI Dual pump installed in the left tank, with a brand new fuel level sensor installed. I did verify it was readinf 40 ohms at one end, and 200+ Ohm on the other end (I dont remember exactly what the top was). Well, the gas gauge shows empty! The shop put 5 gallons in it, and it did not move. They took it to a gas station and filled it up, still showing empty. They ran through all the diagnostics that is in AllData, and now they think the PCM is bad, and wants to replace that.
My question is, how can the PCM just go bad? The gas gage was working when I brough it to them.
Has anyone else experienced this kind of issue?
That sounds retarded to me. Tell them if there so sure it's the PCM, if it isn't the dime is on them!!
You need to get the volt meter out and start taking some readings
Do you have the following:
- Fuel tank connectors RIGHT, Pin A= 5 VDC reference Voltage
- Fuel tank connectors LEFT, Pin C= 5 VDC reference Voltage
- Fuel tank connectors RIGHT & LEFT, Pin B= sensor ground PCM Common
- Pin D = Chassis ground and that is Chassis ground G-401 in the rear wheel on the frame.
If you go to the PCM and read the PCM connector to the fuel pump the pins read like this:
Right tank connector =
A = PCM C2 pin 44,
B = PCM C1 pin 75
C = PCM C1 pin 12
Left tank connector =
B = PCM C1 pin 75
C = PCM C1 pin 12
Read pin A on the right sensor to PIN C on BOTH sensors and you should see 243 ohms
Read the DIC diagnostic routine and see if there are any PCM DTCs set for the fuel system.
Will you be doing this or will the shop be doing this????????
Bill
You need to get the volt meter out and start taking some readings
Do you have the following:
- Fuel tank connectors RIGHT, Pin A= 5 VDC reference Voltage
- Fuel tank connectors LEFT, Pin C= 5 VDC reference Voltage
- Fuel tank connectors RIGHT & LEFT, Pin B= sensor ground PCM Common
- Pin D = Chassis ground and that is Chassis ground G-401 in the rear wheel on the frame.
If you go to the PCM and read the PCM connector to the fuel pump the pins read like this:
Right tank connector =
A = PCM C2 pin 44,
B = PCM C1 pin 75
C = PCM C1 pin 12
Left tank connector =
B = PCM C1 pin 75
C = PCM C1 pin 12
Read pin A on the right sensor to PIN C on BOTH sensors and you should see 243 ohms
Read the DIC diagnostic routine and see if there are any PCM DTCs set for the fuel system.
Will you be doing this or will the shop be doing this????????
Bill
Clif
Tell them if there so sure it's the PCM, if it isn't the dime is on them!! Hi Bill, we should clerify the facts and test already performed!!! Correct!!!
You need to get the volt meter out and start taking some readings We have. Customer didnt!!!!
Do you have the following:
- Fuel tank connectors RIGHT, Pin A= 5 VDC reference Voltage Yes!!!!
- Fuel tank connectors LEFT, Pin C= 5 VDC reference Voltage Yes!!!!
- Fuel tank connectors RIGHT & LEFT, Pin B= sensor ground PCM Common Yes!!!
- Pin D = Chassis ground and that is Chassis ground G-401 in the rear wheel on the frame. Yes!!!!
And we have continuity between the connector pins for the common ground and the 5 Volt reference to the rear and the PCM.. with everything unhooked... And there is no short to ground or Power!!!!
If you go to the PCM and read the PCM connector to the fuel pump the pins read like this:
The car was picked up per customer request after much testing had been done and not verified for the problem at 5:30pm./... Customer would return for further diagnosis next week...
Points and tests not spoken of....
1 Customer performed his own perfomance download on the PCM!
2) EVAP system has been Totally removed from the car per customer request!!!
3) code 1433 for a right hand high voltage etc.. was coming up in the PCM codes...
4) as was a high idle too long code for the idle, only 2 codes period!!!!
The 1433 also has a tie in to the Tank pressure system. which should be invalid now!!!!
There is continuity between the common ground from the PCM and the left and right fuel level sensors as also the tank pressure sensor behind the left fender well!
The left tank sensor has been replaced with a NEW unit and the wires were upgraded BY THE OWNER to an industrial type wire... This connector at the sender reads 183 Ohms............
The right hand Sender is still stock,(was removed 2 times during the build) and replaced as it was functional )... BUT IT READS infinite now!!!!! 1.00000
PLEASE NOTE THAT A TEST WITH THE TECH 2 WAS PERFORMED AND THE GUAGE PERFOMED AS COMMANDED!!!!!!!!!!! Right tank connector =
A = PCM C2 pin 44,
B = PCM C1 pin 75
C = PCM C1 pin 12
Left tank connector =
B = PCM C1 pin 75
C = PCM C1 pin 12
Read pin A on the right sensor to PIN C on BOTH sensors and you should see 243 ohms
(THIS HAS NOT BEEN PERFORMED!!! ALthough a Different sender was placed inline on the RH side and hooked up with the factory connectors and nothing changed...... Please note no connectors have been modified, and the PCM was never taken out of the car or serviced, only the tank level sensors were removed and replaced LH side, the plug ins were never disrupted....... Although the owner and an employee saw it move a couple of times after it got hot??????
Read the DIC diagnostic routine and see if there are any PCM DTCs set for the fuel system. Yes 1433!! we were at the 16 or 17th stage of the trouble tree.. This is were i told the customer that it may be a PCM problem after we used the replacemnent RH sender....
Any comments or diag might be worth your comment as i have lost a day in billable hours for the guage problem.....Thanks BiLL CURLEE
Will you be doing this or will the shop be doing this????????
Bill





Everyone wants to just easter egg in new parts and if they don't fix it, oh well. It might very well be the BCM but,,,,doing all that work and testing, you trouble shot and pin pointed it to one area.
Well Done!
If you have ant theories, run them by me.

Bob
Dale
Last edited by BOUT X; Jun 12, 2009 at 04:04 AM.
Charlie
Last edited by cjlaw73; Jun 25, 2009 at 10:44 AM.
I have been plagued by the 1214 DIC code and had it looked at by my dealer in Ft Meade, small town and very honest with great techs. It reset while there. On all occasions it would show at random intervals, mostly when starting the engine, hot, cold, rain or shine.
When you start some small aircraft its necessary to key the ignition and let the power come to the gauges. Thinking about that and computers in general I got into a new habit. I turn the key and allow the scroll message to cycle and have the warning lights make their cycle. Then I start it. Since doing that I have not had a light. I also noticed that after sitting several days the voltage on the DIC would read low, sometimes 11.6dcv (fairly new optima red top.) Prior to starting I'd see the voltage climb and settle.
What I have come to see after starting and at about the same random interval as the DIC 1214 alert is an alert that appears saying the active handling is warming up. So far in all cases after the warm up light goes away (couple seconds) it's normal. I've come to the conclusion that maybe the computers work a little better if they have a chance to warm up. After seeing a gazillion posts I hope some others can experiment with this idea and hopefully help someone else.
/Ken
Last edited by hill536; Jun 30, 2009 at 10:28 AM. Reason: edit








