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Discussion Starter #1
they all came up on my dash today, second time in as many weeks. Every code, warning that the car has started flashing. Turn the car off, start it again and everything is fine. (Until the next time). What I have done to remedy the situation.
1.) Check battery, 25 mos old, dealers says it's still good and charging properly. Sanded connections.
2.) Disconnect the two grounds in engine comparment, no corrosion, sanded the others and put back.
3.) Took the accordion boots off the two doors and checked the connectors and wires, all seems ok. Pulled on the wires, they seem tight in the connectors, no abrasions on the wires.
Went through the search function here and there are numerous possibilities.

What in the hell am I missing? New ECM?

Before you ask.
10 PCM 1626H Never mind this one, been happening ever since after market exhaust.
TCS U1300-H
40 BCM U1255H
U1096H
U1016H
58 SDM U1300H
U1064H
60 IPC U1255H
U1064H
U1040H
U1016H
U1176H
U1008H
A1 RDCM u1016H
A6 SCM U1300H
U1016H
U1064H
BO-RFA U1255H
U1064H
 

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Jack your car up and check the connections at the PCM. I'm betting you have corrosion in the battery compartment and sand debris has collected in the terminals on the PCM causing an intermittent short. I found a bunch in mine, blew it all out and been fine since.
 

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Discussion Starter #3
Jack your car up and check the connections at the PCM. I'm betting you have corrosion in the battery compartment and sand debris has collected in the terminals on the PCM causing an intermittent short. I found a bunch in mine, blew it all out and been fine since.
Is this the one located behind the passenger tire in the wheel well?
 

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Is this the one located behind the passenger tire in the wheel well?

Yes, I removed my battery and battery tray AND the wheel well liner and found a bunch of corrosion. There is a body ground in the area too, clean that while you are at it.
 

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Discussion Starter #5
Yes, I removed my battery and battery tray AND the wheel well liner and found a bunch of corrosion. There is a body ground in the area too, clean that while you are at it.
I took the battery out last night and did the ground, it was ok but I'll take the wheel off and the plastic cover and check those out. The connectors going into these modules is (are) what I'm checking correct?
 

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I took the battery out last night and did the ground, it was ok but I'll take the wheel off and the plastic cover and check those out. The connectors going into these modules is (are) what I'm checking correct?

yes, your PCM and throttle controller are there. I found alot of fine sand debris and corrosion around the PCM mounts. I just used compressed air to blow the sand out and the cleaned up the corrosion with a wire brush.

Did you remove the battery tray itself? I had a ton of corrosion in on the post. But that doesnt affect the situation just worth fixing
 

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Discussion Starter #7
OK so what am I doing here? Removing these two devices, cleaning them up and checking the plug-in connections, is this correct?

 

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How in the hell do you get this thing out?
I was waiting for this one! :laughing:

If you look at the rightmost bolt in your photo, there is another one around back on the other side. You might be able to see it by shining a flashlight through the side vent or from underneath the car if you remove the lower plastic body tray. In my case I used a Snap-On 1/4" drive ratchet with the right length extension and just had to "feel" my way through it. I find it will also help if you remove two fingers from you left hand before beginning. :D

A good number of people (including myself) found that even after removing the two bolts that attach the outer bracket that the PCM was still "welded" to the rear mounting bracket with just grit that accumulates over time and that results usually in a broken bracket when you try to slide the PCM out - however you may get lucky. I took my time and it still broke. A replacement as I recall was about $12, but it will probably have to be ordered in.

Additional tools needed - many 4-letter words (insert the ones of your choice as necessary).

If it is any consolation getting the rear bolt out is easier than getting it back in!

I also added some anti-seize to the new bracket upon reinstall, but that may even make things worse, but if it is going to break without it, I guess it could not get much worse - time will tell?
 

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Discussion Starter #10
I see that I don't really have to remove the device, I'm just checking connectors so

Ain't nothin' wrong with these, clean as a whistle, notice my cellophane over the other connectors.
 

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I see that I don't really have to remove the device, I'm just checking connectors so

Ain't nothin' wrong with these, clean as a whistle, notice my cellophane over the other connectors.
Yet another possibility if just checking the connectors.

Look in good shape to me.

One thing to check on reassembly... as I recall the orange gaskets now adhering to your PCM need to be pulled off and repositioned over the connectors themselves before plugging back in. I am going by recollection, so some others may chime in to spank me :spanked:
 

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Discussion Starter #12
Somebody better pop up and speak, I'm ready to reassemble.
Yet another possibility if just checking the connectors.

Look in good shape to me.

One thing to check on reassembly... as I recall the orange gaskets now adhering to your PCM need to be pulled off and repositioned over the connectors themselves before plugging back in. I am going by recollection, so some others may chime in to spank me :spanked:
 

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Discussion Starter #14
I guess the hunt continues, that stuff was way too clean. AS some have mentioned in the past just wiggling wires around can do it, I don't have such luck. So I'll keep searching the threads that have this subject, there are quite a few. Thanks all for the help.
 

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I guess the hunt continues, that stuff was way too clean. AS some have mentioned in the past just wiggling wires around can do it, I don't have such luck. So I'll keep searching the threads that have this subject, there are quite a few. Thanks all for the help.
I am sure you already did so, but did you check the battery terminals themselves to make sure they are torqued to 11-ftlbs? I even carry a small torque wrench with me since I notice that my terminals back off that torque value constantly with my Optima Red Top.

There could also be corrosion between the terminals and the wires themselves.

Also did you check the ground on the frame just below the battery?
 

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Discussion Starter #16
I am sure you already did so, but did you check the battery terminals themselves to make sure they are torqued to 11-ftlbs? I even carry a small torque wrench with me since I notice that my terminals back off that torque value constantly with my Optima Red Top.

There could also be corrosion between the terminals and the wires themselves.

Also did you check the ground on the frame just below the battery?
I just hand tighten the terminals. i can see copper all around the terminals so no corrosion there. I've cleaned that ground in the battery box 3 times in the last 9 months. I haven't checked the battery cables where they tie into the starter though. There are a few other grounds I have not checked, they are the concealed ones and I'm pretty sure they are ok. I've checked and sanded and cleaned the exposed ones. I think I'll check that gizmo under the passenger floor panel for moisture, I hear it is susceptible to water but I've never had a leaking battery. I may give another try at the alternator, I had it checked but I think I'll have someone else take a look at it. The guy said my battery is ok, 25 months old. It may be on the short side. It's an optima. I'll take any other suggestions. There is one article by Bill Curlee concerning the ignition and lack of commuication there.
 

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I just hand tighten the terminals. i can see copper all around the terminals so no corrosion there. I've cleaned that ground in the battery box 3 times in the last 9 months. I haven't checked the battery cables where they tie into the starter though. There are a few other grounds I have not checked, they are the concealed ones and I'm pretty sure they are ok. I've checked and sanded and cleaned the exposed ones. I think I'll check that gizmo under the passenger floor panel for moisture, I hear it is susceptible to water but I've never had a leaking battery. I may give another try at the alternator, I had it checked but I think I'll have someone else take a look at it. The guy said my battery is ok, 25 months old. It may be on the short side. It's an optima. I'll take any other suggestions. There is one article by Bill Curlee concerning the ignition and lack of commuication there.
Definitely worth checking the tightness on the Starter Solenoid post. I swapped out my Ignition Switch about three years ago at the same time I checked that. In my case, I was not getting any "light-shows" or codes, but I was trying to track down why my Voltage Gauge kept showing low on the cluster.
 

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Discussion Starter #18
Definitely worth checking the tightness on the Starter Solenoid post. I swapped out my Ignition Switch about three years ago at the same time I checked that. In my case, I was not getting any "light-shows" or codes, but I was trying to track down why my Voltage Gauge kept showing low on the cluster.
How did you get it rekeyed for your car?
 

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I noticed that you have this posted on different forums. I saw that someone directed you to check the harness between the doors. Have you done that? Also, this could be an ignition issue. Your key could be making a intermittent connection while in the ignition. Tell me this, do you have a bunch of junk hanging off your key chain?
 

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How did you get it rekeyed for your car?
I replaced my Ignition Switch (about $75) - that does not affect the key/lock cylinder - it installs behind those - took about 25 minutes to swap it out.

Junkman also brought up a good point about the key contact itself.
 
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