check engine soon
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 790
Likes: 2
check engine soon
My check engine soon light comes on intermittently. Took it to the dealership for a code check. He said "Quad"...which means one of my relays is failing and has burned out that circuit in the ECM. Says I need a new ECM after the failure has been identified and repaired. Doesn't affect the running of the car, just bothersome to have the light on all the time (or sometimes).
Any thoughts on this... anyone else had this problem? :rolleyes:
Any thoughts on this... anyone else had this problem? :rolleyes:
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: check engine soon (emoshn)
What year is your car? Do you know what the code was?
Dealer explaination sound about right for a quad driver failure.
Pete
Dealer explaination sound about right for a quad driver failure.
Pete
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 790
Likes: 2
Re: check engine soon (PeteL)
PeteL. It's a 92. I think I'll try disconnecting the positive lead on the battery for a bit, to reboot, see if that helps. If not...guess I'll have to run down the problem. I'm not familiar with "Quad driver" Can you enlighten me?
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: check engine soon (emoshn)
Quad drivers are a part of the ECM. They are basically transistors that "drive" the actual ground commands from the ECM to the relays / devices that control injection / emmission / various fuel injection functions.
Hard part of troubleshooting this failure is knowing if an outside (of ECM) device is causing (or caused) the fault, or if it is a simple ECM failure. You could easily replace the ECM just to find that the new one develops the same Quad driver failure in short order. Or a replacement ECM may be the correct solution. In either case, the ECM will probably need to be replaced, but the cause (or lack thereof) must be determined first or you can spend a lot of money on blown ECM's.
So, it at least sounds like the dealer understands the problem, question is can they find the outside short (usually) that may or may not have caused it? The usualy answer from a shop would be to replace the ECM, so I think you have at least a reasonable chance with the guys that did this troubleshooting (or perhaps just code reading) for you. In the future, always insist that they provide all codes that they read, and if you are going to work on this yourself - do not reset the ECM - read out the codes first!
Good Luck,
Pete
Hard part of troubleshooting this failure is knowing if an outside (of ECM) device is causing (or caused) the fault, or if it is a simple ECM failure. You could easily replace the ECM just to find that the new one develops the same Quad driver failure in short order. Or a replacement ECM may be the correct solution. In either case, the ECM will probably need to be replaced, but the cause (or lack thereof) must be determined first or you can spend a lot of money on blown ECM's.
So, it at least sounds like the dealer understands the problem, question is can they find the outside short (usually) that may or may not have caused it? The usualy answer from a shop would be to replace the ECM, so I think you have at least a reasonable chance with the guys that did this troubleshooting (or perhaps just code reading) for you. In the future, always insist that they provide all codes that they read, and if you are going to work on this yourself - do not reset the ECM - read out the codes first!
Good Luck,
Pete
