QuestionRoland,
I'm having problems with my 1997 Chrysler Cirrus LXI. Unlike others, mine will start but will only run for a few seconds and stop. One night last week the Mrs. washed her car. She did not wash the motor compartment. On the way home she says the instrument cluster kept turning on and off. A slight rap on the dash would occasionally bring it back. The next morning is when it would start but shut off within a few seconds. Their was the "no bus" indicator on the odometer. I took it to my independent repair shop and after a couple of days of testing, suggested it was the computer. We found one at salvage, install it and he drove it for about 20 minutes. "no bus" was gone. The cluster was still not working properly and he found one at salvage also. I needed the car so I went to get it before the new cluster was installed, and the original problem has returned. I did not even get it into gear and it quit. I did notice the "no bus" again.
Can a faulty cluster cause the computer to fry? Do you have any suggestions? Thanks in advance.
Andy
AnswerHi Andy,
I don't believe the cluster itself is the problem, but rather the communication bus that connects the engine/transmission/body controllers and the collision system and cluster into a single system that is connected by a pair of twisted wires that runs between them via plugs/sockets at each module.
The stop after a few seconds is symptomatic of the body computer not giving the OK to the engine controller because it falsely thinks the car has been broken into and this is how it prevents a theft. If there is a short to ground on either of those bus wires it will temporarily interrupt the data communication until the short is cleared. Being only 2.5V on either wire I doubt it will fry anything.
Using the history of the carwash as possibly relevant, I would wonder if some water might have gotten into the passenger compartment either around the driver's front door opening or the seal of the windshield on the driver side. The body module is under the dash on that side (connected with the fuse box) and if water got onto any of the 3 or 4 plugs that might well have shorted out the system. I would recommend checking the module. Remove the multipin plugs and spray them and the sockets with circuit board cleaner in a spray can available from an electronics supply store. If that doesn't do then an analysis using the Chrysler DRB III test tool (probably at a dealer only) to first look for fault codes and then troubleshoot based on what is found would be the most efficient approach. Throwing expensive parts at the problem is not the way to go.
To get to the module:
remove the end cap on the dash (driver's side)
remove center bezel
remove cluster hood
remove left knee bolster
remove covers from steering column
remove silencer
remove wire harnesses from fuse box
remove three screws retaining the fuse box
pull the box and module straight down from the bracket
Then you can examine the plugs to the bcm on the rear of the fuse box.
Roland
