electrical gremlins - please help!! Airbag Ecu? Edit... Fixed

jamie_z4 · Post by **jamie_z4** » Mon Apr 09, 2018 4:00 pm

Hi guys

Weird problem the indicators on the outside of the car all work fine

The relay no longer clicks though and the indicator signs on the dash don't light up when I'm indicating or the hazards are on

Everything else electrical works including hrw so it's not in transport mode.

Anyone any ideas? Thanks Jamie

Edit.. Fixed. Airbag module was wet through

jamie_z4 · Post by **jamie_z4** » Tue Apr 10, 2018 8:30 pm

cars having all sorts of electrical issues now.

electric windows don't work
roof doesn't work
full beam indicator lamp doesn't work

I left the roof down last week and doing some research - points to the airbag ecu in the centre consol behind the handbrake.

anyone have any experience replacing these ? If so did they need coding?

Scooba_Steve · Post by **Scooba_Steve** » Tue Apr 10, 2018 10:00 pm

Are you sure your battery is ok?

jamie_z4 · Post by **jamie_z4** » Tue Apr 10, 2018 10:06 pm

Scooba_Steve wrote: ↑Tue Apr 10, 2018 10:00 pm Are you sure your battery is ok?

yeah it is new. all issues still present with a mains battery charger connected too.

had the Gm5 module out - replaced with one from another car

removed LCM / headunit checked for wiring breaks,

removed main fusebox and checked all connections / earths - all good.

had car on a 'launch' diagnostic machine - car is not seeing half the ECUs - car thinks there is no roof module/immobiliser/window wiper module etc

Scooba_Steve · Post by **Scooba_Steve** » Tue Apr 10, 2018 10:41 pm

Why does something about the instrument cluster ring a bell? Does everything go through that?

Ducklakeview · Post by **Ducklakeview** » Tue Apr 10, 2018 11:49 pm

Battery is fine. I had it on a BSU so voltage remained at 14v throughout the whole time.

GM5 appears OK, getting good 12v and ground inputs. However in diagnostic only 3 of the 20 or so modules are communicating on the can bus network.

Think this is gonna take a little bit of thought and investigating..

Mike

Ducklakeview · Post by **Ducklakeview** » Tue Apr 10, 2018 11:54 pm

Scooba_Steve wrote: ↑Tue Apr 10, 2018 10:41 pm Why does something about the instrument cluster ring a bell? Does everything go through that?

There appears to be some kind of short between the lcm and the binnacle. When the ignition is turned off, the binnacle backlights stay on, even with key out. Disconnecting the lcm turns them off.

Very weird. I'm thinking either a faulty module cluttering up the can bus with rogue data, a bit like my faulty gap-tech, a poor ground causing the system to track back through the binnacle to a 0v and illuminating it in the process, or a faulty lcm...

Tricky one this. But I will get to the bottom of it.

Mike

jamie_z4 · Post by **jamie_z4** » Wed Apr 11, 2018 6:27 am

Fixed it. Was the airbag module behind the handbrake that had got piss wet through. First thing I did after gettin in off nights is strip the interior to bits (and break everything in the process

)

ph001 · Post by **ph001** » Wed Apr 11, 2018 7:50 am

Well found! How does water make its way into that module just out of interest??

Ducklakeview · Post by **Ducklakeview** » Wed Apr 11, 2018 9:44 am

ph001 wrote: ↑Wed Apr 11, 2018 7:50 am Well found! How does water make its way into that module just out of interest??

~When Jamie leaves the car out in the pissing down rain, with the roof down of course

Mike

ph001 · Post by **ph001** » Wed Apr 11, 2018 10:13 am

Ah!

jamie_z4 · Post by **jamie_z4** » Wed Apr 11, 2018 11:03 am

ph001 wrote: ↑Wed Apr 11, 2018 7:50 am Well found! How does water make its way into that module just out of interest??

As Mike says says, my stupid fault!

It is a bit of a s**t place though, it's a big safety device located in a convertible sports car, just between the seats where water pools in the unfortunate event you accidently leave the roof down....

Rosco01 · Post by **Rosco01** » Wed Apr 11, 2018 12:54 pm

Having the same issues!

How do you remove the airbag module? And did you replace it?

Thanks

jamie_z4 · Post by **jamie_z4** » Wed Apr 11, 2018 3:02 pm

Rosco01 wrote: ↑Wed Apr 11, 2018 12:54 pm Having the same issues!

How do you remove the airbag module? And did you replace it?

Thanks

Hi, you have to remove the whole centre console, there is a guide on here and it involves removing lots of screws etc but it's behind the handbrake under the plastic trim. It's only held in with one bolt though so just unplug it first to see if your issues go away as your removing it from the canbus network then and it will take away the gremlins theoretically like It did with mine.

Rosco01 · Post by **Rosco01** » Thu Apr 12, 2018 2:48 pm

Cheer's Jamie, just seen this. New to this forum stuff and keep missing reply's and responding on wrong thread's!

Managed to get it all stripped out with only a couple of rusty screwdrivers and a plastic shoe horn, absolute nightmare for a novice like me..

Not removed the actual airbag unit as yet, need to get an 8mm socket as I thought the nuts were meant to be 10mm??

Anyway, removed the module wiring and started the car. Radio comes on and window's operable once again!!

Was gonna get a used module off eBay, but can't find one with the same part number?

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