PCM Replacement- '03 C5.
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From: Sunshine State
PCM Replacement- '03 C5.
I replaced my PCM the other day and kept the original to put back in for trips back to the dealers. After removing the passenger side front tire and the access panel inside the wheel well the TAC & PCM are exposed. The only difficult part of the whole deal are the back mounting screws. You have to be a contortionist to get to these. Remove the TAC module (2 screws) and then remove the two connectors from the TAC. Once this is out of the way, remove the two connectors from the PCM. These are self extracting connectors that will back out when you turn the mounting screw. Next, loosen the rear mounting screw in the PCM bracket, but don't remove it. Remove the two front mounting screws from the bracket. The PCM will now slide out towards curbside. Reverse this procedure to install but don't tighten the rear PCM mounting screw and do not install the rear mounting screw for the TAC. This will make the next removal much easier. I just used a nylon tie wrap to secure the back of these modules. It is not necessary to disconnect the battery or any fuses to perform this change.
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[Modified by Korreck, 2:02 PM 6/16/2003]
[Modified by Korreck, 2:03 PM 6/16/2003]
[Modified by Korreck, 2:04 PM 6/16/2003]
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[Modified by Korreck, 2:02 PM 6/16/2003]
[Modified by Korreck, 2:03 PM 6/16/2003]
[Modified by Korreck, 2:04 PM 6/16/2003]
Thread Starter
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From: Sunshine State
Re: PCM Replacement- '03 C5. (1999 White C5 Coupe)
Don't want any hassles over the 3 yr. warranty. I'll also use the original when I want more programming done on the modified PCM.
Bob
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Bob
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Racer
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From: Austin Tx
Re: PCM Replacement- '03 C5. (Korreck)
is not necessary to disconnect the battery or any fuses to perform this change.
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From: Sunshine State
Re: PCM Replacement- '03 C5. (minivette)
There are not any exposed connector pins. There's no reason to dis-connect the battery. If it makes you feel better, do it. I will also say there's no mention of dis-connecting the battery in the service manual.
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Melting Slicks
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From: DFW TX
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Re: PCM Replacement- '03 C5. (Korreck)
If you buy a personal copy of LS1 Edit you can save your original PCM with it. You can then tune the car (or have it tuned) and save the new tunes as well. If you need to go back to the dealership simply put the stock program back in the PCM. When the trip to the dealer is over put the good tune back in.
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From: Sunshine State
Re: PCM Replacement- '03 C5. (Godspeed)
That would work! I prefer to have Lyndon at Westers Garage do my tuning, so I opted to keep the original PCM. Two reasons: 1. I'm not a tuner. 2. Don't have a laptop. 3. Yeh, I know I said two reasons, so I'll quit. Thanks for the input. I do have a question. Why don't we have a 'Save the Wave' icon to put on the end of our posts?
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[Modified by Korreck, 2:54 PM 6/17/2003]
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[Modified by Korreck, 2:54 PM 6/17/2003]
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From: Austin Tx
Re: PCM Replacement- '03 C5. (Korreck)
There are not any exposed connector pins. There's no reason to dis-connect the battery. If it makes you feel better, do it. I will also say there's no mention of dis-connecting the battery in the service manual.
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From: SE Idaho
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Re: PCM Replacement- '03 C5. (Korreck)
There are not any exposed connector pins. There's no reason to dis-connect the battery. If it makes you feel better, do it. I will also say there's no mention of dis-connecting the battery in the service manual.
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Second rule is never work on the high power side of an electric vehicle while holding on to the frame with your other hand. :lolg:
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From: Sunshine State
Re: PCM Replacement- '03 C5. (WhiteC5Vette)
Sir, with all due respect, dis-connect the battery if you will feel better. These are female connectors and it would be impossible to have arcing or contact . If these were male connectors, different story. When you can come up with a valid reason for dis-connecting the battery, let me know. Right now, it appears to be your personal preference. It's still not necessary. By the way, I'm a avionics engineer. What's that first rule again??????????
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From: Vallejo CA
Re: PCM Replacement- '03 C5. (Korreck)
If you remove the screw in the bottom of the fender and then use a long extension and a magnetic socket, you can remove the screw about half way up near the door jamb. You can see this with a flashlight, inside the fender looking past the TAC and PCM. This will let you pull the fender out slightly and give you a whole lot of room to get to the back screws on the TAC and PCM brackets.
That way you won't throw your shoulder out "contorting" yourself.
It should be noted that if you replace the PCM with a new one, it won't run until it is programmed. (I know what you are doing but that is for other folks)
[Modified by EWill3rd, 8:03 PM 6/18/2003]
That way you won't throw your shoulder out "contorting" yourself.
It should be noted that if you replace the PCM with a new one, it won't run until it is programmed. (I know what you are doing but that is for other folks)
[Modified by EWill3rd, 8:03 PM 6/18/2003]
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From: Sunshine State
Re: PCM Replacement- '03 C5. (EWill3rd)
Now you tell me. You can bet I won't forget that. The tie wrap works well but it does look a little tacky. Good thing no one can see it. Thanks for the info.
Bob
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Bob
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