I have a 2001 Bonneville SSEI with 108k miles on it. Intermittantly/randomly the car goes "Ding, Ding, Ding" and the "Right Rear Door Ajar" or "Left Rear Door Ajar" messages appear on the Driver Information Center, then disappear. Sometimes the interior lights come on with them, then turn off. Sometimes it happens repeatedly one after another, sometimes not for several minutes before it happens again. Also intermittantly, the rear windows will on their own go down (sometimes a crack, sometimes all the way). Now, the oil pressure gauge is pinning at 120 when the engine is running. Someone suggested it might be the "Control Module" going bad. Can anyone lend any thoughts/suggestions? Please respond to geodouglas@aol.com. Thanks, George Douglas, Levittown, PA

Welcome to the bonneville club. Sounds like you have some ground corrosion problems. You car has ground buses next to the parking brake release and another on the passenger side same area. Clean these up real good and put some Vaseline or dielectric grease on them to keep them from corroding again. That should fix your problem. Just let us know if it works. If not, we can look at other things. If you have any other questions, just ask.

Do you have problems with any other functions in these doors? Do they lock and unlock correctly, windows go up and down as designed?

Each door in the 2K+ Bonneville is controlled my a module located in each respective door. The input from the door ajar switch will be connected to this module and when a door is sensed as open, a data message will be sent to the DDM (Driver Door Module) as this is the "gateway" module for functions on ALL doors and then fired off over the Class 2 data bust to the instrument cluster.

To help narrow down where the problem is, providing us with this additional information may be helpful.

He mentioned that both doors are doing this. Is it possible the problem is in the DDM. The oil pressure problem may not be related to the door problem and could be a faulty oil pressure sensor.

Testing the Oil Pressure Gauge

• Test the gauge by grounding the wire that leads to the sending unit on the block.
• When the wire is grounded with the key switch on, the gauge should show maximum oil pressure, or the light should go on.
• If either happens, the gauge and wiring are good and the sending unit is at fault.

If your gauge checks out as good, then you may need to replace the sender unit. I believe these cost about $25 or so. This should be located on the right side of your engine below the water pump.

There are no other problems with the functions of the doors. All windows open/close as designed either from the individual door or from the driver door. Door locks function correctly, either by the switch on the front doors or the remote. Thanks for your help!

I would tend to agree with Danthur'* that the DDM is suspect. Diagnosis may be easier with a Tech 2, but likely this isn't an option for you.

It would seem unlikely to me that you would start to have a problem with two seperate modules (one in each rear door) at exactly the same time. Since the problem doesn't involve only a "Door Ajar" message, it is also unlikely that it is the sensors in the doors to detect when they are open.

What is common here is the Driver Door Module. This module, for lack of a better description, interfaces the entire door subsystem to the rest of the car. What I mean by this is that any time the vehicle needs to send a command or check the status of any door, the process goes through the Driver Door Module (DDM). This module is a "gateway" between the door subsystem and the other components in the car. The DDM communicates with the rest of the body modules (not the door modules) over a class 2 data bus.

The door subsystem has its own data bus, referred to as a simple bus. This data bus allows each of the four door modules to communicate with each other, independantly of the rest of the car. Therefore, if one of the modules detects a door is open, a message is sent via the simple bus to the DDM, then the DDM broadcasts a data message over the class 2 bus to other modules in the car that require this information (ie the instrument cluster or dash integration module for interior lamp control). Likewise, if you were to use your remote control to lock or unlock your doors, the RCDLR (Remote Control Door Lock Receiver), also referred to as the RFA (Remote Function Adapter) a class 2 message would ultimately be sent to the DDM commanding the doors to be unlocked. The DDM would then send a message on the door subsystem simple bus to the applicable door modules (depending on how the lock/unlock options are set).

Therefore, it would be my guess based on the information you have provided, that it'* quite likely a problem with the DDM and that the oil pressure is an unrelated problem.

Thanks to everyone for their information!! I have an appointment later this week with a shop that supposedly specializes in electrical problems/repairs. I'll go armed with your suggestions/analysis.

Update: It was a corrosion problem, but not as listed above. There is a wiring harness that is under the front carpeting that comes thru to feed the power driver seat. This harness has ONE connection (the main communications wire for the door modules) that is tan and white. I evidently have a slight water leak somewhere, as the underside of the carpet was/is wet. This moisture corroded this connection. Repair shop cut out, spliced, and shrink-wrapped / sealed new splice. Problem solved!!! Thanks to all for their time and suggestions!!!!

Glad you got if fixed. We have not seen very many problems of corrosion like this either, although there have been one or two. It sounds as though you suffer one of the typcial Bonneville water leaks. There are a few places the water could be coming in. I have yet to see a 2K+ (personally) that didn't have leaking water deflectors on the doors. You may want to consider looking into this, or the other source of the water. This thread will give you the basic information. I've started doing repairs differently since this write-up, but the information will at least help you to troubleshoot. When I have an opportunity, I will be updating the repair procedure to an improved technique.

https://www.gmforum.com/t258329/

I had the exact same symptoms and it also turned out to be corrosion on an extremely cheap wire connector under the drivers seat. There is one wiring cable (harness)running under the drivers seat ( to get at it you must remove the seats, center console & carpet. There are 2 identical tan/white striped wires that are clipped together in a cheap GM quick connector. Mine was green with corrosion from the famed door water leak. I simply stripped a section of each wire and soldered them together and wrapped them up good. All the symptoms went away. I tried uploading a picture, but keep getting an error message saying "server not found". If it helps, just e-mail me and I'll e-mail back a good photo. Note: upon making sure the fix worked, I installed the drivers seat only without installing carpet so I could drive the car a couple days just to be sure it was fixed, and I got a message saying service airbags. It turned out that the passenger seat needed to be installed and the electrical plug under the seat connected - then message went away.
Hope this helps someone.