1999 disco II with 129000 miles, automatic. Symptoms: start vehicle and the shift lever will not move. Brake lights are working, so it seems like the brake switch is working properly. Then after a couple of restarts the shift lever will move and go into reverse. Shift vehicle into drive and it goes forward but light on shift lever bezel and on dash stay in reverse indicator. Pull over and shut engine off and dash and shift lever light on bezel stay in reverse and the ignition key will not come out of the ignition. Leave the vehicle and come back later and the indicator lights are in the park position and key will come out but unit will not start still. Come back sometime later again and the vehicle will start.

Some other things that are happening are turnsignals stay on and don't automatically go off as they should during normal operation and they stay on until the above conditions have run their course.

Also the key faub is not locking or unlocking anything on a consistent basis. I changed the battery and the condition remains the same.

 

See attached. XYZ switch on side of tranny linkage could be out of adjustment. That sends signals to tranny ECU, relayed to BCU, and turns on lights. BCU also controls start inhibit, and turn signals and locking. Since BCU is a "computer" - perhaps the transmission shifting is a higher priority than the turn signal... Would try to adjust linkage first. RAVE shop manual section on automatic gearbox has a hart of voltages at various contacts on the plug for positions. While working under truck and moving transmission selector should have wheels chocked.

 

sound like the xyz switch is out of adjustment

 

if you slide the gear shifter in between where the shifter would normally sit will the gears including park and neutral pop up. if so then it's the adjustment on the xyz. otherwise it sounds like you have an electrical gremlin.

 

Just confirming that the adjustment that is being talked about is the static adjustment. Moving the switch back and forth until the park "P" indicator show's up in the lcd screen on the dash, key on engine not running. I did pull the xyz switch apart and it was clean and dry inside. I very carefully checked the contacts and cleaned. Reassembled and reinstalled switch and took on a test drive. It lasted longer before showing symptoms this time but they did come back. The signals stopped working which let me know that the problem was not corrected. Drove home parked in the driveway and turned ignition off and "D" was still in lcd screen and lit up on shift bezel. Key would not come out of ignition and driver side window would not roll up as non of the others would either. So the real question is do I replace the xyz switch as all the problems seem to be directly affected by that or is there some more diagnosic work needed before throwing money at a switch and hoping this will make all well.

 

are the M and S lights blinking? are you stuck in 3rd gear when you have problems?

 

I'm not stuck in 3rd while driving, but once vehicle is parked the M and S lights have started blinking, not all the time just every now and then. I had this problem a while ago and it was a wire in the wiring harness pushed back in the connector going to the transmission connector plug. The disco drives ok once symptoms start you are stuck once you put in park and stop the vehicle.

 

After sitting last night the M and S lights were blinking when key was turned to the on position. Once disco was started they went away. Now P is indicated in lcd screen on dash and it started right up with windows all responding to their switches.

 

if the xyz were the problem you would be stuck in limp mode. (3rd gear with the M and S lights blinking) since this is not the case, we can rule that out as a problem. Im thinking you have two seperate problems, the window switches not working and the transmission malfunctioning. Do you have any water leaks on the driver side A pillar? has your truck ever been flooded? Im thinking the transmission ECU is the next thing to check out. as you know its under the driver seat below the stereo amp held in place by 3 nuts. you can seperate it from the amp with those plastic screws and take it apart with the metal tabs. i would make sure its clean and not soiled. maybe spray it with some electrical cleaner. check that wiring harness again to make sure everything is tight including the 3 bolts that hold the computer to the floor. not sure off the top of my head but one of them could be a ground.

 

So without enough time and resources to continue diagnosing my problem I took it to an independent shop near my work. They were able to replicate the problem and they found that the majority if not all my problems were due to communication issues with the body control module. My question to the forum is, is there only one body control module on the vehicle? I have done some research and called the local dealer and the body electronic control module has a retail cost of $691.99. I cannot find another module on the vehicle that is referred to as a body control module. The independent shop says the repair will cost $2700.00 including the $300.00 in diagnostic fees it took to find the problem. I come from a service back round and have no problem with the electrical diagnostic charge, it took them 3 days to have the problem present itself. My issue might be the fact that they want $2400 for a dealer part that cost $691 plus tax and $1700 to install a part that I believe sits under the front passenger seat. Please lay some knowledge on me reguarding this subject. Thank you.