I'm in the process of converting my 92 968 to a mostly-track car, so I removed the passenger side air bag to save some weight. I ran across a post of somebody in need of an air bag control module, so I sold it to him. Now, after finally finishing the engine rebuild, I can't get the car to start - there's no signal coming from the DME to turn on the fuel pump, or to fire a spark. Also, the blink test doesn't work - the CEL illuminates when I turn the key to the start position, but it doesn't blink when I press the throttle to the floor. I've tested a host of items, including installing a borrowed spare DME, and nothing has helped, so I'm beginning to suspect that removing the air bag control module may be my culprit.

To be clear, I'm NOT talking about the unit behind the dash that houses the air bag itself - I'm talking about the control module buried farther behind the air bag under the dash. It's held in by a set of tamper-resistant (VERY tamper-resistant - I had to use a chisel to get them off - that should have been a clue...). Does anybody know if removal of this unit could shut down the signals coming out of the DME? I'm getting +12V at terminal 86 of the DME relay in the fuse box, which is the ignition switch signal, but nothing at terminals 87 and 87b. If this is indeed the root cause of my problem, does anybody know how to bypass the connectors for the module to trick the system to thinking it's still there? Thanks.

 

if you remove the air bag control unit, you need to jump the black and white to the black and red....at the 6 pin connector to the air bag unit.....vinie

 

+1 jumper goes in the female connector between pin 3 & 4.Make sure it is well secure since if it does come out while your driving the car will stall.

 

Thanks for the quick response - it sounds like this may in fact be the cause of why my car won't start. But could you please clarify a little - there are three connectors that go into the air bag control unit - I believed they are colored blue, pink, and white. In order for the car to think the air bag control module is still connected, I should have to bypass some of the sockets in one or more of these three connectors. If this is what you're referring to, could you tell me which of the three connectors the wires you're describing go into?

There is also a large, flat connector, with an orange plastic strap, that connects the air bag unit itself to the wiring harness. You have to connect a pair of the sockets in this latter connector, number 3 and 4, I believe, to keep the "!" warning light from staying on. I don't remember the wire colors that go into these sockets, though (I'm at work, so not near my car). But I suspect this is the connector you're referring to, because it is a six-pin connector. I've already jumpered sockets 3 and 4 on this connector. So, this is NOT the source of my problem. Thanks again.

 

Ernie,

Nope, this isn't it. I've already done this. The connector you show in your picture is the connector the connects the air bag unit to the wiring harness.

I'm talking about something different, but seem to be having a very hard time being clear. I'm talking about the air bag control module, which is a metal box that sits way back behind the air bag under the dash. It is a MAJOR PAIN to reach, and is held in by four very tamper-resistant nuts. The only reason I removed it was that I came across someone who needed one, and I figured I wouln't be needing mine since I had already removed the air bag, so I sold it to him.

As I said in my post above, this module has three connectors going into it, and they're colored pink, blue, and white. I have some pictures of it, but they're on my home computer. There must be some sockets in one or more of these connectors that I need to jump to make the car think the module is still in the car. I suspect I may be in uncharted territory here, because I doubt many people, even racers, ever remove their air bag control module, because it weighs less than a pound. Thanks.

 

you already jumped the black and white to the black and red.....

 

I don't remember the wire colors offhand (I'm at work), but I jumpered the sockets in the connector Ernie shows in his post above (sockets 3 & 4).

But as I keep saying, this isn't the right connector. I need to find a way to make the car think the air bag control module , which I removed and sold, is still connected to the car. The connector you guys keep referring to is between the air bag unit (the unit that houses the air bag itself, shown in orange in Ernie's diagram) and the harness.

 

i AM referring to the connector that would plug into the air bag control unit....its behind the glove box....did you also take out the alarm contorl unit....the 15 power goes into the air bag unit then to the alarm box...i have a 968 in the shop and have done this many times....when you get a chance snap a picture of what you have and we will figure it out.....vinnie

 

I'll post a picture of the unit I removed when I get home. I didn't touch the alarm control unit (the one mounted next to the DME). I don't think my no-start problem is related to my alarm, because I'm getting +12V at terminal 86 of the DME relay - I'm pretty sure that if the alarm were activated, it would shut off the signal to this terminal, which activates the ignition.

The air bag control module has three connectors, a white one, a pink one, and a blue one, whereas the connector to the air bag itself which Ernie posted a picture of has only one, six-pin connector, which I've already jumpered as Ernie's picture shows. I need to find out which pins in which of the three connecors for the ABCM I need to jumper to fool the car into thinking the ABCM is still there.

 

A. Have you removed both airbags? If not, do so first. Do NOT proceed without removing the airbags.

B. On connector labelled 1, try jumpering pins 11 to 12 and see if you get spark.

C. If that doesn't do it, remove 11 to 12, and on connector 1, jumper 7 to 8.

D. If that doesn't do it, jumper both sets, 11 to 12, and 7 to 8.

I don't know what color connector 1 is. If you get it wrong, and you leave the airbags in you could set off one of the bags. The wire colors are:

Pin 7 - white
Pin 8 - green
pin 11 - black/red trace
pin 12 - black/white trace

 

Doc,

First to answer your question, I've removed the passenger side air bag, but not the drivers side, which obviously is in the steering wheel. I assume there's no way to remove the drivers air bag without removing the wheel, right? I'm planning to get a new, non-airbag wheel, but haven't done so yet, so for the time being, I still have the stock wheel in the car.

OK, here are a bunch of pictures to try to get everybody on the same page:

First, here's the air bag module, which of course houses the air bag itself, which I removed simply to save some weight:

Attachment 697451

I've peeled back the electrical tape that I had over the connector plug on the left.

Here are the two connectors that plug into the back of the air bag module. I inserted a 2 ohm (iirc) resistor across each of these years ago to disable this air bag, because I had young children at the time (I hadn't removed the air bag module when I bypassed the connectors using the resistors - I removed the module more recently as part of the track car build project):

Attachment 697445

This is the flat, 6-pin connector in which I've jumpered pins 3 and 4, per Ernie's instructions. The wires are black/white and black/red.

Attachment 697446

One thing I didn't remember correctly: I thought one side of this connector goes into the air bag module, but it doesn't - it goes into the wire bundle leading the the air bag control module's connectors. So, apparently the orange box in Ernie's diagram refers to the air bag control module, not the air bag module as I had thought. But in any event, jumpering these two pins has not solved the no-start problem, so it appears that I need to do something more or different.

So, the three photos above all pertain to the air bag module. This isn't what I'm concerned about, as I understand that all you need to do if you remove the air bag module is jumper pins 3 and 4 in the flat 6-pin connector. But I went a step beyond this - I actually removed the air bag control module (ABCM), shown in the picture below:

Attachment 697447

You can see it has three colored 12-pin connectors, pink, off-white, and blue, going from left to right (top to bottom in the picture).

Here's a close-up of one of the tamper-resistant, serrated nuts that hold the ABCM in place. I had to use a cold chisel to remove these. It would have been a lot easier if I was smart enough to remove the glove box:

Attachment 697456

Here are the female ends of the three 12-pin connectors that plug into the ABCM, also colored pink, off-white, and blue:

Attachment 697449

So, what I think I need to do is find out which pair of pins in which of the three connectors in the photo above I need to jumper. Doc, I didn't see any number designations on these colored connectors that uniquely identifies one as "1", one as "2", and the third as "3", so I don't know which of the three connectors is 1, per your instructions. Do you know where its label might be? Maybe I missed it.

Also, I need to understand whether I need to jumper some pins in the ABCM connectors in addition to the two pins I've already jumpered in the flat six-pin connector in the third picture from the top, or if I need to jumper some pinds in the ABCM instead of the two I've jumpered in the flat six-pin connector, or do I need to do something else entirely. The bottom line is this: I've tampered with my car's air bag system, which I suspect has caused my DME to go into some sort of shut-down mode, which is preventing it from sending a signal to energize the fuel pump, and to initiate a spark, preventing my car from starting. So, I need to find a way to trick my car into thinking my air bag components are still in the car and connected.

OK, I hope this clears things up. Thanks, everybody, for your help.

 

just make sure you are jumping the wires that go into the car harness not into the air bag harness.....make sure the black and white has power with the key on.....vinnie

 

I'm almost positive I'm jumpering the correct connector - it's the half with no numbers designating the pins. Thanks for the tip to check that the black and white wire has power with the key on (relative to ground, I assume). I'll check that tonight. There's definitely +12V at the DME harness connector (can't remember the pin number offhand) with the key on. I think it's something like pin 43 - it's described in the very first step of the DME troubleshooting guide in the manual.

 

The drivers airbag removal is in the WSM. It's not difficult.

A. Remove the plus wire from the battery, wait 30 minutes from then to proceed.

B. Using a T-8 bit on a ratchet, remove the two screws on the rear of the steering wheel hub that hold the airbag to the steering wheel hub. You can locate the recessed screws with your finger on the hub, facing toward the dash.

C. once removed, you will see the red connector which connects the ignition pill circuit to the airbag firing wire. Remove this red connector from the hub.

D. Set the airbag on the floor, facing up and tape over the red connector.

I don't know the relationship between the colors and numbers of the airbag controller. If you look at each connector, I think you will find they are numbered somehow. The wire receptacles will also be numbered on the connector. Verify with the wiring colors.

 

Doc,

Thanks for the info. And duh, yes, I will very easily be able to tell which connector I need to jumper the pins on by your description of the wire colors.

Just one more question before I start - Do you know if the jumpering you're describing needs to be done in addition to the jumpering of pins 3 and 4 on the wide, flat 6-pin connector in Ernie's diagram, or in place of it? In other words, do both connectors need to be jumpered? If you don't know, it's not that many combinations, so I could easily try them all, especially with both air bags removed. OK, wish me luck...