Airbag light fault

[smoggy]

Hi
Mercedes E200 classic auto

My airbag warning light started coming on intermittently and I think I have found out what causes it but I don't know the cure.
If I sit in the passenger seat and start the car the light goes out,
if I then take my weight off the seat for about 10 seconds the light
comes on, if I then put my weight back on after 10 seconds it goes back off.

Can anyone give me some pointers on how to cure this problem

Thanks in advance

 

[stats007]

Welcome to the forum Smoggy .

It sounds like the pressure mat switch in the seat is dodgy - it works on diminishing resistance with pressure - the Airbag light staying on signals that the system is deactivated for the passenger - usually for child seat recognition.

If you know your VIN you can look up your car here for parts diagrams - part numbers may be out of date however.

 

[Hibbo]

On my w124 the main airbag connector is in the passenger footwell - don't know if it's the same on yours - could you be inadvertently pressing against this when you're on and off the passenger seat?

 

[smoggy]

Hi stats

Thanks for the speedy reply.

I had a look on that site couldn't find the part in question but
I live close to a Mercedes dealership so if I need the part
it would probably be easier to go there.

Is it a simple job to replace it

 

[smoggy]

On my w124 the main airbag connector is in the passenger footwell - don't know if it's the same on yours - could you be inadvertently pressing against this when you're on and off the passenger seat?

Hi Hibbo
Thanks for the reply, I have retried it and it definitely looks like it is in the seat.

 

[stats007]

You may want to have a quick look to see if any wiring is loose or a bad connection first - one chap had electric seats that weren't working and discovered the motors weren't connected just as he was about to order the switch unit at £100.

I haven't had to replace one of these so it could be a complete pain if you need to take the seat apart. If you post the first 6 digits of your VIN we'll know what model you have (124 / 210 / 211 etc) and someone may have done this themselves.

 

[smoggy]

I'll give it a good check over tomorrow when its light to see if its not something simple or loose as you suggest.

My Vin number starts WDB210035

 

[stats007]

I had a quick look - it appears the seat needs to come apart as the sensor is sandwiched between the covering and bolster.

There are also a few different sensor pads depending on your full VIN but MB price is around £50 for the occupant sensor, £100 with child recognition .

Let's hope the problem lies elsewhere!

 

[smoggy]

Hi stats007

Had a look under the seat and yes it does look like a disassembly of the seat
However I aimlessly wiggled a few wires and it has seemed to cure it although it may only be temporary, I'll just have to cross my fingers and hope for the best.

Once again thanks for taking time out to help me it was much appreciated.

Regards.....smoggy

 

[GT Main Man]

Hi Smoggy,
No need to buy sensor mat as you will find if you remove the seat there will be 1 , 2 ,or 3 broken wires where they come through the seat frame below the cusion. Rejoin the wires & no more flashing light .
Please get in touch if you require any help.
Regards GT Main Man

 

[eric242340]

On the 220 model we change at least two passengers SRS pressure mat sensors a month and it does mean dissassembling the seat. Bit of a time consuming job. Why the passengers seat and not the drivers seat, that goes wrong, I dont know.