QuestionHi, I just purchased a 1998 Chrysler Sebring JX Convertible and the digital odometer reads "no bus" when the the power is on. The car runs and drives and the lights on the instrument panel all work, but the gauges are non-functional. Having read similar problems on the forum here I tried disconnecting the radio and the airbag control module, but with both disconnected it still displays no bus.
There is some indication of water on the driver's side floorboard in the front and back, but otherwise no apparent electrical issues and the engine still seems to be communicating with the ECU, as it exhibits fast idling when the engine is cold and compensates for the A/C compressor being turned on. All the fuses appear to be in order except for one of the two airbag fuses (#16 on the fuse panel, 10 amp) blows within a few seconds of being replaced when the engine is running.
Any advice you can offer would be appreciated, as other than examining the apparent short in the airbag system I don't even know where to start diagnosing this problem. Thanks!
AnswerHi Tristan,
I suspect that the problem is at the instrument cluster itself, on the blue plug, pins 7 and 8, where the ccd bus wires are located. I would first check the socket pins where they connect to the circuit board as one of the the solder joints may be 'open'. You could try heating up the joints with a soldering pencil to close the joints to see if that re-established the connection and restores the function of the gauges*. The wires stem from the body computer but also are spliced to the data link connector (under the dash by the steering column) where you should be able to do a diagnostic code readout using a code reader. If the code reader works, then the wires are patent to the splice from the body computer to the splice so logically would have to be connected to the body computer. However if the code reader doesn't work, that implicates the connection to the body computer (white plug pins 1 and 11) or the body computer proper.
That #16 fuse connects directly to the airbag control on a white wire at pin 2 of the gray plug. You could check the downstream side of the #16 fuse socket, after removing the gray plug at the control, to see if the wire shows a short to ground. If not, then the airbag module proper has some sort of an internal overdraw that is blowing the fuse. The airbag control module is hidden at the bottom of the center stack, and it would be more convenient for me to xerox and postal mail you 2 pages from the manual than to type in the procedure to get to it. Also there are figures that would be helpful.
So use the 'private' option of the follow-up question to tell me a postal address. When you are checking whether the code reader will work, you may get a fault code that explains what might be wrong with the air bag system, so let me know if that is the case. You can often get a free code readout from an Autozone parts store or similar nationwide chain.
Roland
*The procedure for removing the cluster is about 20-steps, so I would rather xerox copy that, as well, rather than typing all that in and you would also get several figures. The air bag module is also involved in that process.
PS Please 'rate' my answer.
