QuestionNo Bus on the odometer display, cycled the key and nothing, have a brake light, abs light, airbag light, no blower functions in the heating ac systems, radio does work locks and keyless entry work as well. please help. i replaced the main fuse module and nothing. Tom
AnswerHi Tom,
When you say you replaced the 'main fuse module', do you mean you replaced the entire "intergrated power module" box that is in the engine compartment? (That must have been very expensive. May I ask why that was done?)
Did all this start at once, or did it come on slowly over several driving trips.
History of the problem, please. And what else has been done/tried?
Do you hear the fuel pump run (humm) for a second, from inside the fuel tank, when you turn the key to the 'run' position?
When you have a helper turn the key to the 'starter' position, do you hear/feel a click coming from the starter motor relay located in the integrated power module?
Would you please review the other questions that I asked in my first answer and give me a response to any of those that aren't answered already?
Thank you.
PS I am attempting to find out exactly how much is working and how much isn't working so as to see if this involves the starter motor, the entire digital bus, a single fuse/many fuses. I need to know exactly how 'dead' is the electrical system.
Roland
Here is my first answer:
Hi Tom,
The bus is the digital communication system that knits together a half-dozen or so modules that need to share informantion for the proper operation of the electronics involved in the engine/transmission/body computer/cluster/etc/ There are a number of ways that the system could be inactivated.
Can you give me the year of the vehicle and the engine size (L)?
What is the history of the problem?
And did the 'no bus' show up on the odometer spontaneously or was it in response to your request for a fault code readout by using the ignition switch?
Can you tell me which accessories work and which don't? I assume there is no starter motor action.
When you turn the key to the 'run' position do you hear the fuel pump hummm for about 1 second from inside the gas tank?
How about the gauges/warning lights on the cluster?
If you haven't tried yet: turn the ignition switch:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if it shows anything other than 'no bus'.
Roland
Roland, yes i replaced the entire ipm. I obtained a flow chart from a chrysler garage and followed it and it led me to a no ground on Pins 25 and 33 of the front control module. that is why i replaced the ipm. There is no history on this car. nothing at all from the ignition no fuel pump no starter relay clicking only lights on the dash. No head lights no power window no turn signals no emergency flashers. the only thing that works is the radio and the keyless entry for the locks and the trunk opener. The problem started when it was parked over night. i ran the car on Sunday parked Monday morning at about 3am. Went out to it on Monday afternoon and got the no bus signal on the dash and that is where we are still at. I am a ford master tech so i am experienced with electrical problems however i have no manuals for this chrysler. I hope this info helps you with what i am working with. Tom
Hi Tom,
I just found your response in the 'reader comments' section. That is an area I check every other day or so, but otherwise I don't get any direct notice of a response. Sorry for the delay.
I will review all these past questions/answers and get back to you soon. If you have anything new to report about where things stand with the vehicle, please do so by asking a new question. Don't use the reader comments.
Roland
