SRS air bag lights...
Discussion
Autopower.se - that was it. Thanks for the reminder - I've now bookmarked the instructions for next time (Google Translate to the rescue).
https://www.autopower.se/mekartips/mekartips.asp?d...
https://www.autopower.se/mekartips/mekartips.asp?d...
drdino said:
dave_s13 said:
Only trouble is I've got to pay someone £15 a pop to get the codes cleared.
Did you try to clear them by disconnecting the battery and leaving it like that for 10-15 mins?Bought a resistor, diode and capacitor off ebay for about £5 delivered.
When that arrives I'll disconnect the battery, make up the emulator and see if that clears it.
So yesterday the airbag light went off randomly and worked both times I drove the car that day. Now it's back on again.....grrr.
This makes me think it actually doesn't need resetting with a scan tool once everything is working.
So I tested the seat sensor with a multimeter and it seems to be working in that the resistance changes with or without someone on the seat. Tried the emulator trick and no joy.
That leaves this box of tricks as the being the likely culprit
Not on eBay though, need to check some breakers and what not.
This makes me think it actually doesn't need resetting with a scan tool once everything is working.
So I tested the seat sensor with a multimeter and it seems to be working in that the resistance changes with or without someone on the seat. Tried the emulator trick and no joy.
That leaves this box of tricks as the being the likely culprit
Not on eBay though, need to check some breakers and what not.
Penelope Stopit said:
Now that you know that a reset isn't needed.....With the car running and the light out you could work your way along the loom with a wiggle and a waggle to see if there is a break or bad connection somewhere.....the light will come on if there is a open circuit somewhere
I've kinda done that but could have a closer look.Only place I can find that box of tricks is off a random polish website.
I'm half tempted to just run it til the mot expires in June, wack it on Ebay as is and just buy a new shed. The bloody thing has only got 46k miles on it and it's like new inside but it's worthless with this bloody light on.
I finally found, purchased and received a used PPD unit as per previous picture. Plugged it in and....zilch. Light still on!!
Fortunately I can send it back with it only costing me the postage.
Checked the wiring to thay box, earth is good but it's getting zero power. Why the fark didn't I check that 1st!! This points toward a possible fault with the wiring to the SRS control module or the module itself. So next job is to find that and try and trace the wire back to check for power at the required pin. It's then either a broken wire, or a f
ked SRS module. Can't help thinking it'd be worth bodging a live feed from somewhere else into that box to see if that doesn't he trick.
Grumble....this is turning into a right pain in the arse for what is essentially a bit of a pig of a car.
To add to my woes the EML came on a couple of days ago but I cleared that off with my basic obd tool. It's had a bit of a lumpy idle since I bought it a couple of months ago. Looks like the short term fuel trims are a bit off and the downstream O2 sensor output looks dodgy. Managed to get a used sensor anyway see if that sorts it. If I can't get this airbag light off though it's going on eBay for someone else to mess about with, while it's still got 6months+ MOT.
Fortunately I can send it back with it only costing me the postage.
Checked the wiring to thay box, earth is good but it's getting zero power. Why the fark didn't I check that 1st!! This points toward a possible fault with the wiring to the SRS control module or the module itself. So next job is to find that and try and trace the wire back to check for power at the required pin. It's then either a broken wire, or a f
ked SRS module. Can't help thinking it'd be worth bodging a live feed from somewhere else into that box to see if that doesn't he trick.Grumble....this is turning into a right pain in the arse for what is essentially a bit of a pig of a car.
To add to my woes the EML came on a couple of days ago but I cleared that off with my basic obd tool. It's had a bit of a lumpy idle since I bought it a couple of months ago. Looks like the short term fuel trims are a bit off and the downstream O2 sensor output looks dodgy. Managed to get a used sensor anyway see if that sorts it. If I can't get this airbag light off though it's going on eBay for someone else to mess about with, while it's still got 6months+ MOT.
Edited by dave_s13 on Thursday 6th December 19:35
Edited by dave_s13 on Thursday 6th December 19:37
So. Thought I'd bring this to a thrilling conclusion!!
Bear in mind through all this I'd convinced myself the actually passenger seat occupancy sensor must be ok, given the low miles on the car, as new condition of the seat and the fact its resistive output changed with sat in Vs not sat in states.
After trying a DIY emulator (see prev links in the thread) and an occupancy sensor module without joy I tried an airbag control unit from a breaker. Still no joy.
So bit the bullet and paid a nice chap to come round and plug it into a proper bit of kit. At this stage I'd put the original airbag ecu back in. This confirmed the ECU was in fact faulty as was the occupancy sensor itself (not the module is tried to replace). So £50 lighter I put the new ECU in place and he checked the codes again, only thing left was the seat sensor. Getting there now.
So, armed with this new info I decided to try some buggering about with the bits I had, with a bit of trial and error I managed to knock up an emulator that actually works! Turns out the seat sensor module needs to see somewhere in the region of 15ohms and it sends the ok signal. Result.
This means you need 3x 56k resistors in parralell, not just the on as per the previous links.
A bit long winded but anyway, if you now Google this issue it might lead back here and help someone else. You can't actually buy emulators for these cars btw....you can for everything else ever made.
And yes I know it will now kill small children sat in the front but it's a risk worth taking in this case.
Tldr: car had 3 faults when I bought it
1. The main airbag ecu was faulty.
2. The occupancy sensor was faulty.
3. Driver's seatbelt buckle wiring damaged.
Airbag ecu was £19 delivered off the bay + £75 in total for the code reading.
Car has a reprieve now and I'm quite pleased with it now. It runs and drives pretty sweet really.
Bear in mind through all this I'd convinced myself the actually passenger seat occupancy sensor must be ok, given the low miles on the car, as new condition of the seat and the fact its resistive output changed with sat in Vs not sat in states.
After trying a DIY emulator (see prev links in the thread) and an occupancy sensor module without joy I tried an airbag control unit from a breaker. Still no joy.
So bit the bullet and paid a nice chap to come round and plug it into a proper bit of kit. At this stage I'd put the original airbag ecu back in. This confirmed the ECU was in fact faulty as was the occupancy sensor itself (not the module is tried to replace). So £50 lighter I put the new ECU in place and he checked the codes again, only thing left was the seat sensor. Getting there now.
So, armed with this new info I decided to try some buggering about with the bits I had, with a bit of trial and error I managed to knock up an emulator that actually works! Turns out the seat sensor module needs to see somewhere in the region of 15ohms and it sends the ok signal. Result.
This means you need 3x 56k resistors in parralell, not just the on as per the previous links.
A bit long winded but anyway, if you now Google this issue it might lead back here and help someone else. You can't actually buy emulators for these cars btw....you can for everything else ever made.
And yes I know it will now kill small children sat in the front but it's a risk worth taking in this case.
Tldr: car had 3 faults when I bought it
1. The main airbag ecu was faulty.
2. The occupancy sensor was faulty.
3. Driver's seatbelt buckle wiring damaged.
Airbag ecu was £19 delivered off the bay + £75 in total for the code reading.
Car has a reprieve now and I'm quite pleased with it now. It runs and drives pretty sweet really.
Edited by dave_s13 on Monday 17th December 15:26
GreenV8S said:
Now you've got it working, will you replace that screw terminal connector with crimped or soldered joints?
I should really shouldn't I.It's all taped up securely and not flapping about in the wind or anything (which would probably lead to the wires failing in the screw terminal). I'm tempted to leave it for now but will probably go back and do it properly at some point, it's not making my teeth itch or anything :-)
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