Computer board has been replaced twice.

MARTY246

MEMBER
1998 JEEP GRAND CHEROKEE LAREDO

Computer board on 98 Jeep Grand Cherokee Laredo has been replaced twice. It blows the board right after you install the new one and crank it up. No one can tell me what is causing this yet they keep taking my money. Any suggestions?

Quit while going down hwy. Told it was the computer board. Replaced with new board, cranked engine board bowed. Replaced again and same thing happened. No one able to tell me what the problem is.

3 Replies

DRCRANKNWRENCH

MECHANIC
3,380 POSTS

You must have a short somewhere. Unfortunately a short coming off the ECU is a lot of circuits to check.
I am giving you the data lines for the truck. I am also giving you the PCM wiring diagram which has the dataoutputs and sensors labeled very clearly. There are 3 of them marked 1of3, 2of3, etc.
They will be the wires you want to follow more than the datalines asI understand that this is the computer board that keeps getting fried.
I gave you the PCM for the 5.2L engine, the data lines are not engine specific. If you have a different engine, let me know which one you have and I will give you the proper PCM diagrams.

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