How to temporarily by-pass the crash control module is shown here by demetek for testing if faults then disappear
Location: Main fuse box in the engine compartment.
problem solved
copied info of his questions + my comments to his problems:
My '89 E34 525i developed an alarm problem 4 years ago when the alarm horn was bipping intermittently whilst driving & it got worse over the next 2 years. During a routine dealer maintenance the car wouldn't idle unless (any) door was open. (Door pressure switches are original). Dealer finally suggested the front most module under the rear seat was faulty= GM. (This module operates the sunroof/electric windows etc. & all work perfectly).
Module was tested (independently)... "no prob". I eventually replaced it with another 2nd hand one & it went good for 2 years. Now the problem is worse, & as before, only when the car is at full operating temperature, so even after a few miles it starts to bip & the engine will cut momentarily. Whilst driving it beeps on & off & hazard lights flash... not good to drive around town... or anywhere.
ALSO, whilst still hot, & the car left parked (locked or unlocked), the alarm will suddenly go off. Opening any door/trunk will stop it, but it commences again as soon as the door is closed. Turning the key in the door lock several times will sometimes stop the alarm when the door is eventually opened. BUT SOMETIMES... the alarm will sound WHEN AN UNLOCKED DOOR IS OPENED!!! (Confused so far... yep, so am I). Otherwise, leaving a door/trunk opened until the car cools down seems to eventually stop the alarm from sounding, then it will sit for days without a murmur! Yesterday after a trip, whilst it was sounding... I removed the module & the alarm kept sounding! I've owned the car for 17 years, & there's no immobiliser that I know of. For further confusion, fitting the 'offending' module to another car it works perfectly!!! The dealer can't find a prob & 2 X INDEPENDENT AUTO ELECTRICIANS, DITTO.
Am I up for a new module? Or could it something else?
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crash alarm relay?
Just a shot into the dark: pull the crash alarm module in the fuse box and drive around and see what happens. The brown one, crash alarm geber is written on it, you cannot miss it
I had a problem that my hazzard lights came on by their own, it was also this relay. And read this Emergency flashers blinking when opening door
operation of crash alarm : "After deer crashed into me, I knew the crash relay worked, because the inside lights came on, flashers came on, doors unlocked, at the same time as the check control filled up with alarms about missing lights. But I didn't need to do anything to drive away. Ken 97 328i, 95 540i
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As I sit on my veranda with a cold beer, I raise the can & mutter, "Here's to the 'bimmerboard" before each sip!
Would indeed appear to be the relay. Before starting the car I removed the relay, looked at it & replaced it, & let the car idle for 20 minutes.... no prob so far. Went for a 50 mile drive... NOT a 'beep"! Returned home & removed it again & gave all 9 pins an emery rub & went for another drive. On return opened & closed all doors, locked & unlocked the car etc...
Now I write to say "THANKS, SHOGUN, you're a legend"!
Dirty contact could have been the problem but I'll replace the original one anyway.
What ever did "we" do in the 40's & 50's & before the internet. But cars weren't so complicated then either. Now I'm an "expert" on another piece of modern machinery! Confused no more. Jim