No bus code appearing when I turn the ignition off. Radio and power locks/trunk switch isn't working. Please help

Checked the smaller fuses on driver side dash panel/under hood. Unsure how to check the bigger black fuses. Disconnected battery, unplugged cd changer. Still nothing. Replaced the fuse in radio. Still nothing. Would like to get radio and locks working again ASAP.

Module issue?

 

The "bus" is basically a communication wire that connects all the computers and the things the computers control including the instrument panel, the radio, etc. There are three main computers: engine, transmission and body plus some smaller ones like the ABS system and the airbags/seatbelt modules. There's no simple fix like disconnecting the battery or a fuse that is going to cure the problem. The problem could be internal to a computer module or one of its connections or the wire itself.

Given that the door locks and radio are affected, it's probably a problem with the body computer. May be the computer itself or a connector or something else. These things require a computer to analyze them. Somebody with a DRB III who knows how to use it might be able to locate the problem. Because of the expense of those things and the training required to use it properly, they'll charge you probably a hundred bucks to hook it up to the car and run the diagnostics. Dealerships have the equipment, some high quality independent shops may also have it. A run-of-the-mill code reader won't be able to do the job.

 

Thank you for the detailed breakdown dkotter. You really know your stuff. Is there a specific name for the body computer? Is that the PCM? It seemed like right when the radio went out, it happened when I was driving to work, I had the radio on and I heard a popping sound (like popping a sealed plastic ziploc bag) when the radio went out. I don't know if that's just coincidence or if there is a correlation. But if you have any info on that please let me know but I'm sure I'll have to contact a Chrysler dealership and have them use that DRB III to run a diagnostics. I went to an auto parts store a week ago and their ordinary code reader couldn't do it. I know why based off what you just said. Thanks for the help.

 

the radio is prob taking out the bus network unplug it see if the network comes back up.

 

I unplugged the radio and cd changer beneath the radio. When I start the car I can hear something turning over from the direction of the radio/cd changer. It sounds like it wants to boot/start up the cd changer or radio

 

The body computer is formally named the Body Control Module or BCM. The engine computer is called the Powertrain Control Module, or PCM, and also called the Engine Control Module, or ECM. By the way, replacing one of these computers with one pulled from a car in a junkyard is very unlikely to work. It'll need to be programmed with the VIN and mileage and it'll need to make friends with your anti-theft system if there is one.

If the CD changer is still making noises, it's not completely unplugged. The plug to disconnect the radio from the bus is a small plug with a thin wire or wires. It's not like the other plugs back there which are bigger with multiple wires coming out.