Ok, long story short, I think my PCM stopped working. My OBD-II box wouldn't read any more and a dealer's DRB-III wouldn't either. Dead as a doornail.
I thought maybe a '98 concorde 3.2 could supply its modules to replace mine (a '99 with 3.2 motor). And I replaced all 3 because they check each other's VIN coding, or so I've heard. The VIN has to match or the modules lock themselves out?
So I got the PCM and TCM (located under hood, driver's side front, remove the headlight to get at them, they are side-by-side with the fuse box, take out the TCM first) and the BCM (body computer, located on fuse panel) with the piggyback RKE (remote keyless entry) module. The 98 had no SKIM (Sentry Key Ignition Module - AKA chip-key reader), but my 99 does. I reasoned that it would still work, just that the sentry key function would be lost. I removed my SKIM module.
So the OBD-II never did wake up - but now the car flashes the lights when in 'run' position (only). The motor starts, but dies after 4 seconds.
The security system has kicked in? Unlocking the passenger door with the key doesn't help. I don't have a remote. The electric lock switches on the doors don't function any more. Anybody have any ideas? It troubles me that the OBD-II port is dead. Are there any other modules? The only other computers I could trace are the ABS brake module (located on the drivers side, front, almost directly under the headlight), and the infinity sound system amp module (pass side footwell).
My next attempt will be to swap '99 Intrepid PCM/TCM/BCM from a 3.5 motor (I have a 3.2) and see what happens then. Unless I find a 99 concorde first, but Intrepids are more plentiful around here...
Incidentally, the Infinity sound system amplifier module is located above the front passenger footwell side kick panel. It's very hard to get at (high up) - but I could feel it and removed it in the junkyard to see what it was. I doubt that module would have VIN checking. But if you are looking for it, it's up there, held by 2 - 10mm head screws at the bottom and has 2 wire connectors on the bottom.
Also, as a side note, the odometer changed to a different value after the PCM/TCM/BCM replacement, but I had left the dash cluster intact. So the mileage must be stored in the BCM...
ONCE I get it going, it is going to get a purple-sparkle (over black) paint job., like this red one and change the lettering on the rear and sides to ... G R A P E ... The Concorde is such sleek looking car with that oval grille like a racing ferrari, too bad it won't run...
I don't know the answer to any of your questions (other than - yes - the mileage is stored in the BCM).
But I wanted to make you aware that the '98 TCM is unique in that any given '98 TCM is either for a car with autostick or non-autostick. Later years the TCM looks at the cluster to see if it's autostick or not and acts accordingly. I doubt that is your problem though - the '98 and later TCM's are interchangeable as long as you pay attention to the autostick/non-autostick thing for the '98 TCM. Also, as you may realize, for any year, the TCM may be programed for the "regular" gear ratio *or* the 300M Speical/2.7L gear ratio - the only implication of that is that if you get the wrong one, the ratio for the speeodmeter and odometer will be wrong.
'98 LXi - Later Concorde gages (black w/ chrome rings)/'99 LX - LHS gages (white) - HIR bulbs
Thanks - that's good to know. I don't know why I'm having such problems with this car but these computers are very hard to diagnose and I'm an engineer. But I'm also cheap and I don't have a wiring diagram (yet) and only a basic OBDII. I don't see why the car companies can't make money as there is very little a DIY guy can do, without involving a highly paid expert of some kind (and this is a 10 year old car..!)
I will admit that cars do run better with the modern EFI, better than the old Bosch FI and waaaay better than a carb. Better mileage, more power, more features.
But when it's dead, it is D.E.A.D. Period. Start walkin'...
Yes, when the vin's dont match, the ECM will lock after 3 attempts to start it. That shouldnt happen, unless Im missing something here, if you replaced BCM, ECM, and key reader. TCM shouldnt matter, those are interchangeable, except for '98...has to be autostick or non-autostick.
Mileage is stored in the BCM.
If you still cant communicate with the computer, you may have a wiring issue, and not a computer issue. You would think you would be able to access the new ECM once you replaced it.
Last edited by Daytrepper; 03-16-2009 at 11:01 PM..
OK I got the Grape going today. The reason it took so long is it was really cold here and winter just seems to go on forever this year. Still have huge snow piles.
It WAS a fuse... #19 to be exact. Interior lights..?? PLUS OBDII and Security system, apparently.
I replaced it and the OBDII lit up..!!
Left the car for an hour with key in the 'RUN' position to let the PCM reset itself from 'lockout' mode?
Still no start - flashing lights - security system...
So I locked/unlocked the passenger side door from the outside (with key) a few times.
NO more flashing... looks promising...
Turn the key and VROOM - plus it runs more than 4 seconds.... YAAY..!!!
Thanks to everybody who made suggestions - especially the fuse guy - sometimes the most obvious solution is totally overlooked. Especially when there is no reason for a fuse to blow. It was the first one I checked - the Haynes showed Fuse #19 in the wiring diagram for quite a few PCM things. Oh yeah, plus the interior lights..?