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Frank87
01-14-2020, 04:57 PM
I got some airbag trouble on my E34. Common troublemaker the slip ring has already been replaced with a NEW dealer item a few months back. I replaced it properly and put it in the "middle" position with the wheel also in the middle position. The steering wheel was able to do a full left and right turn without the feeling you are snapping wires.

The universal ADS interface I am using (not a BMW computer) says "driver airbag firing circuit fault".

Assuming the slipring is ok (I will see if i can measure it), what other common airbag issues are known for the E34?

I have both a driver and passenger airbag.

632 Regal
01-22-2020, 09:17 PM
Search does not work. Use any search engine and look up tight steering. That was what the title was when I posted it here. Might come up might not. II'll try to check back tomorrow.

genphreak
01-25-2020, 12:40 AM
Neer seen this before, but check the wires that connect to the wheel- the orange connector on the late models seem weak, low gauge wires that can be pulled and may go high/open circuit. Maybe have a look at the wiring diagram too, under the back seat atop the driveshaft hump is the airbag module, I'm not sure if it is involved with firing the wheel bag but I think it is for all. It probably has a transistorised switch to fire the bags depending on the impact location. If this is the case, the wiring may be routed under the rear footwell (blanked off wires can corrode where they join), or under the GM, check again for corroded connectors, particulalry where the wires from the loom connect to the connector pins on the loom side of the plug.

Frank87
02-03-2020, 06:43 AM
Update:
- checked the connector under the steering wheel. Was solid but I reconnected it just to be sure;
- removed some of the coppergrease on the back of the slip ring where the brush slides just to make sure it is not accidentally isolated (although coppergrease should be able to act as conduit;
- checked the module under the rear seat, disconnected it, cleaned the connectors, reconnected it. Looked fine but did this anyway;

Reconnected the battery, reset the airbag system and the fault is totally gone. Already did a 1.000km trip to Poland.

I guess one of the 3 above reasons was the reason for the general error and SRS light.

One more project remains before attaining perfection... replacing the IHKA for an overhauled one.

632 Regal
02-03-2020, 07:03 PM
The slip ring on mine gave me the greatest headache for a couple years. Not on Goldie (1994) that was in Michigan for 10 years came from georgia but the southern one (1995) from Georgia also. When cold the grease would freeze and bust the SRS (Orange) switch/connector. Search slip ring. I do not see as I can see any brushes going on in there. The only slip ring I can think called that is the little brass ring that was fitted where contact was made I ended up using graphite. Look up slip ring.

genphreak
02-23-2020, 01:30 AM
The slip ring on mine gave me the greatest headache for a couple years. Not on Goldie (1994) that was in Michigan for 10 years came from georgia but the southern one (1995) from Georgia also. When cold the grease would freeze and bust the SRS (Orange) switch/connector. Search slip ring. I do not see as I can see any brushes going on in there. The only slip ring I can think called that is the little brass ring that was fitted where contact was made I ended up using graphite. Look up slip ring.

Nice work! Keep it up over there Frank87. May the rain clouds part wherever you travel!

* If I see a fault, I usually use some connector cleaner and then when dry, some conditioner on the contacts, not between. The ol' slip rings all need to have the new grease applied by now, as per 632 Regal's earlier posts on the subject

632 Regal
02-24-2020, 12:38 PM
http://www.bimmernut.com/forum/showthread.php/44534-E34-530-540-power-steering-heavy