airbag system

Anyone know if there is a special procedure to reactivate the airbag system, 1999 Taurus? Replaced the crash module unit, lamp was on solid, no flash. My reader doesn't do srs. Figured for 40 bucks used I'd give the module a shot. Part is not available as new any longer. My repair book mentions reprogramming frequencies user 1 and 2, also setting a clock. Light is still on, checked all the fuses beforehand, all good. Thanks.

The reprogramming mentioned is just for the User 1 and User 2 radio presets, along with setting the clock. They really have nothing to do with the airbag system.

Since the light is still on, are you getting a Lamp Flash Code (LFC) shortly after turning the key to the Run position? As best I can tell, either the light should do a bulb test and go out, or it should provide a LFC then stay on if there is an issue. From the factory service manual:
"After all service, verify the AIR BAG warning indicator. This means turn the ignition switch to RUN and count the flashes. If the AIR BAG warning indicator comes on continuously for six seconds and then goes out, and if no LFCs flash within 30 seconds, the air bag system is functioning properly and all malfunctions have been serviced. Refer to Diagnosis and Testing."

-Rod

Yeah, I kind of thought that, didn't make sense to see it there though. Anyway, the lamp is solid, no flash code. I may have to spring for a srs capable unit.

Ok, borrowed an Innova code reader 31603 from someone, this unit supports srs Taurus 96 - 12 according to their site. According to this unit, my 99 does not support srs communications. That is the message the reader gives out. Tried it on my son's 98 Taurus, btw with the wacky methanol capable motor, all functions work, abs, srs, etc. Haven't been able to find anything about this, will call the local Ford dealer Monday and speak to a mechanic about it. As I posted before, it is a solid lamp, no flashes.

Since you're not getting any flash, there is a chance that the airbag module is faulty, which would also explain why the scan tool was not able to connect to it.

Was the light on before you replaced the "crash module unit"? What was the reason you replaced the module?

-Rod

Ok, I re-read my service manual and there is a piece in there, I missed it several times before, about the ngs receiving a no communications error. I have to run some voltage and resistance tests on the connector for the module and there are a couple for the dlc. I replaced the module because the light was on solid, I didn't run any tests beforehand. The original module and the replacement could both be bad or not, I will see after I run these tests on the connectors. The airbag lamp was intermittently coming on and going off, no flash codes. Like I posted before these modules are no longer available from Ford. Found this one online for 40 dollars, figured for that amount just try it. Guy told me he would refund if it was found to be no good. He told me it was not from a wrecked vehicle, have to take him at his word on that. All other tests, obd, abs, work off the dlc so most likely it is good. I will post back with results, may take a few days.

Good find on the diagnostics for the no comm error. Good luck!

-Rod

Ok, I think I've found the issue. The hot always pin on the crash module connector is only giving me anywhere from 1 to 4.5 volts, spec calls for 8 - 18 volts. The fuse in the power distribution box is good, I changed it out for the h of it. Wiring diagram shows circuit 609, o/y, running thru another connector into #16 power box. I pulled up the power box, popped off the bottom cover, looks to me like 3 o/y wires under there. I checked the diagram for power box, did find another o/y wire for the abs module, circuit 532 fuse #13. As much as I could see under the box, I did not disconnect any battery leads, looks to me like (2) o/y wires into the #16 spot. Not 100%, but certainly looks that way to me. There is one connector the 609 passes thru on way to the crash module, I believe I found it, but haven't taken it apart, has a bolted cover or something. what do you think about pulling the #16 fuse, then running a jumper wire from the battery to the connector on the airbag to ee if it works?

If you have a fused lead or tap off of a the fused side of another circuit, I'd say it's worth a try. At least that will give likely give you the opportunity to confirm for the seller that the module he provided is working. Just make it a loose, precarious wire so you ARE inclined to figure out the issue with the factory wiring rather than just living with the "temporary" repair. ;)

-Rod

Ok, I was thinking about pulling the #16 fuse, then running a fused jumper from the battery to the connector wire. What does the low voltage reading indicate to you? I'm not a big electrical guy. All looks in pristine condition, no work has been done, nothing has been disturbed. Maybe connector is corroded under power box, can't tell for now. Never had an electrical issue before this. I'll have to disconnect power leads from box, then figure out how to fully open bottom of box to expose wiring connections to the fuses, if that's possible.

The low voltage can't be caused by a short, right? Wouldn't the fuse blow if that was the case?

Correct, the low voltage cannot be caused by a short, but it could be caused by a corroded connection.

Did you check the voltage at the fuse terminals to see if fully battery voltage is making it to the fuses at least? At a minimum that will help you determine which direction to start your search, either between the fuse and the airbag module or between the fuse and the battery.

-Rod

Thanks, I'll check that

Alright, ran the jumper, all was good. Found the big connector under the dash, unbolted it, pulled it apart, put it back together. thought maybe bad connection there, no good. Putting out about 5.70 volts at the airbag conn, up from last time. Going to find the pinouts for the big connector check, volts thru there. Also I'll pull the dist box up, check that out. Crappy weather coming, I'll wait til it warms a bit. Could do it in garage, pain though.

All fixed. Harness out of dist box splits, one split runs down into engine compt, splits up, my o/y wire was not there. 2nd split runs into the fender behind battery. first thing pull connector off of crash module, no inadvertent airbag release wanted. Pulled lf wheel, fender liner, harness is strapped up along fender, runs down along the strut into a plastic formed openable case which guides it thru two 90 degree bends toward the firewall. Cut all the tape, removed plastic case, checked the o/y wire where it first enters the case, all good to there, still 12 volts. Was going to go into pass compt to disconnect large connector and check there, but instead decided to cut the tape and loom off where the harness enters the firewall from the wheelwell. Lo and behold 3 volts only on the o/y wire. Ran my fingers back along the wire towards the strut, felt a small bump, pulled the wire to the top of harness, a little bluish blister bump, somehow this wire corroded in this spot. This was in the middle of the plastic case There are quite a few wires in this harness, this one was in the middle of the group. Never seen this before, no damage to the insulation. Pretty weird. Cut it out, soldered, shrinkwrapped new piece of wire in place. All other harness wires in this spot looked good. Factory fresh all good to go.

That's an awesome find! Good job, and thank you for following up with what you discovered.

-Rod