2003 Jeep Laredo Freaky Circuit

JOE_BETTINI

MEMBER
2003 JEEP GRAND CHEROKEE LAREDO
6 CYL
4WD
AUTOMATIC
84,000 MILES

I'm have a heck of time trying to find the source of my freaky circuit.
The freaky circuit controls:
- Power Windows
- A/C operation
- The Right readout of the overhead console, (Temp, Mileage, .)

The only way to reset this is to mementarily disconnect/reconnect the battery. This will reset it for a few hours to a few days. There seems to be NO PATTERN as to when/how it disables itself. I can tell it's gone down when the right side of the overhead display shows - - - - instead of the temperature.

I've tried to find the correct circuit/sub-system via the schenmatics via the Haynes manual, but no luck. I even tried replacing a relay. Does anyone have an idea what this is, or even what to try next?

Please help. I can't tell you how bad it gets when in the summer the A/C turns off and the windows won't open. Always seems to happen in heavy traffic here in Chicago.

1 Reply

SERVICE WRITER

MECHANIC
9,123 POSTS

I would think that codes are being set when this problem is happening. By you clearing them by battery diconnection, it clears them (memory). Might be worth picking up a code reader, to get a start on this. IF you do this, post the codes.

Mitchell has a pretty good set of diagrams, but would take some time to study. There are the code procedures in there as well.

Sounds like it is heat related based on the heavy traffic.

Try to access the BCM when everthing is good and warm it with a hair dryer to see if problems are recreated. Sounds like a BCM may be on it's way out.
But wouldn't jump to that conclusion.