Chrysler Repair: Body Control Module, shaft sensors, 1994 chrysler concorde

Question
Roland I have a 1994 Chrysler Concorde and for some reason the heating/ac unit and ALL window control switches stopped working.I went to a electrical shop where a hot wire was temporarily connected to the window fuse slot in the fuse box,I left the wire in for several days and it apparently drained the battery.I bought a brand new battery and the car still will not start. I've been told by a auto service shop that the BCM has disabled the fuel injectors and for whatever reason there's no response from the unit when attempting to reset. The Auto shop says I need a new BCM. also what could have caused my ac/heating unit and ALL the power window controls to stop working and most importantly HOW DO I FIX IT without buying a $375.00 BCM?

Answer
P.S. I should have also suggested that you test the current draw on each of the four fuses that are powered by J fuse, using an ohmmeter so that you can find the circuit that discharged the battery and was probably the one that blew the J fuse. Use an ammeter to see what the current draw across each fuse socket is when the ignition is off (what is called an "off draw" measurement). But you could also simply measure the resistance from the downstream side of each fuse socket with the J fuse removed and all 4 fuses removed so that the fuse socket that shows the lowest resistance to ground will be identified as the bad actor.  That should then direct your attention to the circuit that needs repair/needs to have its fuse removed until you can repair it, while you try to get the engine started and running again. I would doubt the BCM is your problem. The engine controller will shut donw the fuel pump, the injectors and the spark if it doesn't get the sensor signals from the engine (crank and cam shaft sensors) or the autoshutdown relay which is what actually turns off those items can fail and refuse to power them up even though the sensors are o.k. The theft system is part of the BCM and so if the sensors were o.k. and autoshutdown relay was o.k. then I suppose the BCM could be bad due to a faulty anti-theft subsection, but I don't think I'd buy into that without further verification.
Roland
Roland



Hi Carlton,
I am in the middle of a big repair job myself but let me see what I can do.
The power windows are pretty clear as to wiring, but the heater/ac is complex and depends on whether you have the automatic temp control or convintional control panel and system. So let me give you a place to look for the power window problem and maybe it will also fix the A/C-heater.
The power distribution center (rectangular box under the hood) has a 40 amp fuse labelled J. If you had to jump power a fuse in the cabin to get the windows to work then either that fuse J is blown or the ignition switch section that it powers has a bad contact and needs to be cleaned up or replaced. So check J. If J is o.k. there should be power from it to the ignition switch on a pink/black wire, and when the ignition switch is in the run position power should be found on a black orange wire at the switch that goes to several fuses in the fuse block: F20, F21, F23, and C1. And those fuses then power: the back up lamps-ABS if you have it-the heater a.c, the power window system, the air bag system, and another aspect of the heater a.c., respectively. So that J fuse or the switch itself could  explain the original problem.
As for the no start, the only way that the bcm could have a relationship to that might be if the car has a security system and it has somehow been triggered to prevent a theft. So if you have a security system try disarming it. I believe you only have to lock and unlock the front foor using the key to do that. But check the owners manual on that issue if you have one. The other possibility is that there is a separate failure of the engine controller. So I would do the self test for fault codes: turn the ignition key on-off-on-off-on and leave it on (doing this in an elapased time of 5 seconds or less). Then see if the check engine light which remains on begins to flash and pause. Count the number of flashes before each pause, make a note, and then when you have all the number of flashes, group the numbers in pairs in the order they came out to form two digit fault codes. Code12 will mean that you disconnected the battery recently, code 55 will be the last one out which means end of readout. Any other code is relevant, particularly 11 and 54 which have to do with ignition spark and fuel supply sensor signals for example. But all codes are relevant. You can retest for codes as often as you like to make cerain you have them correctly. If you disconnect the battery and reconnect all the codes will disappear except 12 and 54, but then when you try to start the car any relevant code will be detected and set in the memory.
I am not going to take any question at the Allexpert site until I finish my job, but you can write me at rfinston@hotmail.com and I'll try to get back to you.
Roland
P.S. I have the manuals for the security system and the data bus (both engine contoller and BCM use this bus) so that may be of help later. You can get a translater for the the codes: www.allpar.com/fix/codes.html
so that will help in figuring out why the no start as well.
Goodnight.
Roland