Air bag light flashing - Saxperience

tiger1983 · 28th April 2015, 12:25

Any ideas on what could possibly be the cause or if it's a case of a scan tool needed.

I've done a vts conversion (the donor car had no warning lights at all) I've used all the vts seats, airbag ecu, dash, wires, you name it I've used it! Now ive got the annoying flashing airbag light!

I've checked the pretensioners atleast 4 times, multimeter showing just under 3 ohms (had looked up online and apparently between 2 and 3 ohms is good), I've checked all the connections behind the dash, unplugged and re plugged, checked the connections on the airbags and even changed the drivers side to a spare I've got and still got this annoying light!

stevo67 · 28th April 2015, 13:07

Under 3 ohms then the light will flash,the airbag does a self test anything under the 3 ohms the ecu regards as a fault.Cut the plugs off under the seats(making note of what wire goes to what wire)Then solder them together.

tiger1983 · 28th April 2015, 15:26

The solder idea was my next idea, I've had the battery disconnected for the past 3 hours so I'm going to reconnect and hope it sorts itself but if not then I'll cut and solder tomorrow. I had read that between 2 and 3 ohms was considered as a good but I only saw that on one site rather than researching more

CarlStinson · 28th April 2015, 17:50

buy yourself some resistors, plug into each plug one at at time, to find your fault, mine was the airbag its self

tiger1983 · 28th April 2015, 18:15

Had thought of resistors but never really looked into how that works and if it actually effects the way the airbags work etc. I know the airbags are crap in any accident from experience but I know my pretensioners worked in the past and always say they kept me alive so will be wanting everything working as it should... looks like abit more research tonight and finding somewhere local that sales resistors before the solder job

CarlStinson · 28th April 2015, 18:21

i have one, plugged into my airbag wiring under my steering column, this tricks the airbag module in thinking every things ok, so doesn't display the warning light, failing a MOT check, you dont have to cut anything just order one of ebay, or go to maplins and get one for about £1, unplug the connector and put the two prongs into the connector that goes under the carpet, and the one thats under your steering column that leads to your airbag, if the light goes out then you know where you need to be looking if you want to get it fixed

tiger1983 · 28th April 2015, 18:57

Is it any particular resistor that I'd need so I can go looking for some on ebay? The town I'm in is full of coffee shops, no one attempts work on their own cars in the area but as I say, I've never looked at doing it that way but if it still keeps the system working as it should then it's good enough for me, soon as I've found the problem I've got no problem getting it fixed but tried everything I can think of today other than taking airbag ecu out and trying another one

CarlStinson · 28th April 2015, 19:42

everything but the faulty part will work, heres the one i got off ebay worked great

link
get yourself one and then its just process of elimination of the 3 connections for the airbag module

tiger1983 · 28th April 2015, 20:24

Nice one!! Thanks! Would it be worth buying a few just in case there's more than one fault? I'm gonna go on a hunt now about using these resistors, I'm guessing if I just use one but have 2 or more faults, I'd be needing the same amount of resistors to get the light off. I've got 5 seperate connections and the 2 plugs on each air bag (plugs under front seats, 2 on passenger end of the dash in the fuse area and 1 under the steering column)

CarlStinson · 28th April 2015, 20:35

Yes get 3 that covers each one, you only need to put one resistor per plug, one prong in to each connector you don't need to put one into the other plug under the seat that goes to the pretension, as you have disconnected it from the loom, just the one that goes under the carpet, back to the airbag module

tiger1983 · 30th April 2015, 15:23

Will get them ordered next week, managed to get the car booked in for a few checks for dvla next week and the mechanic said he'll have a quick look over things whilst it's there bit won't be pulling things apart so if he don't find the problem then I'll be getting the resistors sorted

tiger1983 · 7th May 2015, 07:50

Right, an update on this situation. The garage had the car yesterday to do all the dvla checks for the conversion so while it was there I asked them to check and delete any fault codes (I plan on buying my own scan tool soon as I work out which I need). The garage said it had recorded 3 codes, 2 deleted without a problem but one came back as "trigger 2 open circuit", the garage said it is more likely under the seat and also recommended soldering the wires so that's today's plan but was wondering if anyone else could put any light on this trigger 2 circuit incase the solder doesn't solve the problem. If it's still flashing this evening then I'll definitely be ordering resistors aswell.

stevo67 · 7th May 2015, 17:30

Was the airbag ecu from the vts?if so the airbag could have gone off at some point in the past and the ecu has logged the fault.

tiger1983 · 7th May 2015, 18:59

Quote:

Originally Posted by stevo67

Was the airbag ecu from the vts?if so the airbag could have gone off at some point in the past and the ecu has logged the fault.

That's what's bugging me as I have swapped out everything from the vts (ecu, dash with passenger airbag, wiring, seats, you name it I took it, to the point the only thing on the car that is not anything to do with the vts is the shell). When it was in the vts there were no lights at all and I checked every bulb before refitting the dials, seats were stored under the stairs so no one would of got near them without me knowing and I've also tried a 2nd drivers airbag. Wires were soldered today under the seat and I've ordered resistors so hopefully next week I can eliminate things. I have got a known working ecu from the 1.1 setup but not programmed to see the passenger airbag so that also kept the light flashing but have also wondered if the earth on the ecu is good and if that would set off the flashing dash light if it's a bad earth. I've even pulled out the stereo as I read that some audio equipment can cause interference but again no luck.

tiger1983 · 13th May 2015, 11:27

This is getting annoying now haha. I've tried

*Resistors, no luck!
*Unplugged and test continuity along the lines, drivers seat seemed abit dodgy
*just about to splice a spare loom in place and plug that in (cancelling out the vts loom) and see what happens, will update on the progress of that in a little while.....

But for now, has anyone got any pics of the plugs at the airbag ecu on a mk1 vts 99 plate? I've looked at the plug of the vts and the plug from the 1.1.....vts has an earth wire whereas the 1.1 didn't also the vts has 3 pins in the brown plug whereas the 1.1 has 4. As I said originally, the vts before being stripped had no warning lights and all bulbs were working, nothing has been tampered with and everything has been swapped over so I'm starting to think I've wired something wrong but considering its all basically plug and play, I'm getting abit lost and until I work out which diagnostic tool to buy, it makes it a little more arkward.

Update...
*Spliced the 1.1 loom in place, still flashing.
*Resistors into 1.1 loom, still flashing
*Swapped airbag ecu (which I knew was 100% working) to match the 1.1 loom, still flashing!

MartinObviously · 15th May 2015, 17:13

Trigger 2 open circuit.

That's one of the 2 front crash sensors on the chassis legs. so the airbag ECU under the dash isn't getting a signal from it.

tiger1983 · 15th May 2015, 17:27

Quote:

Originally Posted by MartinObviously

Trigger 2 open circuit.

That's one of the 2 front crash sensors on the chassis legs. so the airbag ECU under the dash isn't getting a signal from it.

Thanks! Any tips on what to look for to possibly fix it? Could it be something I've not wired right during the conversion?

I've never had to deal with airbag systems so this is all new to me but enjoy learning it all.

stevo67 · 15th May 2015, 21:53

Try clearing the airbag ecu of any stored fault codes.

tiger1983 · 15th May 2015, 22:34

Quote:

Originally Posted by stevo67

Try clearing the airbag ecu of any stored fault codes.

Will be trying that the minute I get a scan tool, I had thought the issue may have already been fixed after soldering the wires but not resetting itself. I should have some clear funds Tuesday so will be ordering an all in one scan tool and hopefully be able to reset things by the end of next week before I go to the extreme of pulling the car apart again.

MartinObviously · 17th May 2015, 22:20

I've no idea where to start.

What I do know, is the airbag ECU is a live system. it doesn't store any codes. As soon as the fault is gone, the light goes out.

I suspect one of the pins which is on the ecu, but not on the loom, is the cause.

Remove the airbag ECU and all the airbags.