Need help w/1994 ECM
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Need help w/1994 ECM
Need some advice/help with my father-in-law's 1994 LT1 Coupe. I'm a C5 +C3 owner, but I'm going to jump in and help him with a BIG problem with his C4. Apparently, he had some electrical issues and the car would not run. I advised him to take it to a Corvette-specific garage in Houston, but he took it to a Dealer!!! Mistake #1. They have had it for over 2 months, replaced the computer ($1700, which I think is a rip-off!), but the "corvette mechanic" there says he does not have the ability to "hook up to the computer and program it". What a bunch of ding dongs. I am now telling him to let me load his car up and fix it myself. He's hesitant, even though I have performed 2 complete frame off restos on C3's, and modded my 2002 Z06 with no issues.
My questions is: Is there anything "special" about 1994's that I need to consider? I seem to remember that this model year was the changeover toward OBD-II diagnostics? I think the "plug" under the dash is shaped like the OBD-II plugs, but still uses OBD-I software? I'd like to know a little more before I commit to this. I'm confident in my skills, but need the advice/research help of the experts (C4 guys), this dealer is NOT even interested in fixing this thing. Your help is appreciated!!! Thanks guys.
My questions is: Is there anything "special" about 1994's that I need to consider? I seem to remember that this model year was the changeover toward OBD-II diagnostics? I think the "plug" under the dash is shaped like the OBD-II plugs, but still uses OBD-I software? I'd like to know a little more before I commit to this. I'm confident in my skills, but need the advice/research help of the experts (C4 guys), this dealer is NOT even interested in fixing this thing. Your help is appreciated!!! Thanks guys.
Burning Brakes
Joined: Nov 2005
Posts: 908
Likes: 1
From: Colorado Springs Colorado
Did he replace the CCM or ECM? The CCM is behind the radio and holds the odometer setting. It is also an unholy terror to replace. You need a tech-1 with a mass storage cartridge to reprogram the miles. I don't think a tech-2 will do this on pre-96 cars, but I may be wrong. If you drive on a new CCM for (I think) 100 miles, you loose the ability to re-program the milage, or at least I seem to recall reading that somewhere.
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OK, you're right! Its the CCM. After listening to what my father-in-law said, he did mention the terms "tech 2", so it must be the CCM that was replaced. He also talked about the radio and dash being all torn out, so that too leads me now to believe it is the CCM.
So, how do I get my hands on a "Tech 1" device? And what kind of job am I getting into?
And does 1700 seem WAY too expensive for what we're talking about?
So, how do I get my hands on a "Tech 1" device? And what kind of job am I getting into?
And does 1700 seem WAY too expensive for what we're talking about?
Burning Brakes
Joined: Nov 2005
Posts: 908
Likes: 1
From: Colorado Springs Colorado
Like I said, I think you need a Tech-1 with Mass Storage Cartridge. They are very hard to find. I have one, maybe another CF member closer to you has one and can help you out.
I don't understand what they thought they were doing replacing the CCM if they didn't have any way to program it?? Your odometer and your VATS codes need to be set with a new CCM.
I don't understand what they thought they were doing replacing the CCM if they didn't have any way to program it?? Your odometer and your VATS codes need to be set with a new CCM.
Burning Brakes
Joined: Nov 2005
Posts: 908
Likes: 1
From: Colorado Springs Colorado
I looked at my 92 FSM and it looks like you can set the VATS key value without a programmer. This won't help with the odometer setting, but should get you past a no start condition if the only problem is the VATS setting in the ccm. Do you have a FSM? Check section 9D for the proceedure, yours may be different than my 92.
BTW, I have to drive through Houston in two weeks on my way to Florida. If you still haven't located the Tech1 with MSC, I suppose I could stop in with mine.
BTW, I have to drive through Houston in two weeks on my way to Florida. If you still haven't located the Tech1 with MSC, I suppose I could stop in with mine.
Last edited by scranage; Nov 10, 2006 at 04:55 PM.
