Resistor 12/4 Front Passenger Airbag resistanc to high

frogdr1ver

Member
Joined
Aug 27, 2021
Messages
11
Reaction score
2
Your Mercedes
Vito W639 2011
Hi,

Wondering if anyone can help, I've got this fault on my van Resistor 12/4 Front Passenger Airbag resistanc to high. It's reading 15.9ohms. Any ideas where to look to see if there's a loose connection etc. I've recently changed from a 2-1 to a 1-1 seating arrangement and told the van that it no longer has a centre seat.
 

Tony Dyson

Senior Member
Joined
Aug 26, 2018
Messages
4,038
Reaction score
2,585
Location
God's Country
Your Mercedes
2014 C 220 CDI W204 OM 651
Look for a resistor in the kit you've disconnected/removed from the vehicle for if you remove one of two parallel connected identical value resistors from a circuit, the measured value will double giving you a higher reading than you previously had with the two resistors connected in circuit.

i.e. a resistance reading of two parallel connected resistors rated at 250kΩ each will read 125kΩ, this will provide a TRUE response as an input to the monitoring software. Remove one of the 250kΩ resistors and the test reading will double to 250kΩ, this will provide a FALSE reading to the monitoring software, it's just the way Ohm's Law works.
 
OP
F

frogdr1ver

Member
Joined
Aug 27, 2021
Messages
11
Reaction score
2
Your Mercedes
Vito W639 2011
  • Thread Starter
  • Thread starter
  • #3
I've only disconnected the centre seat belt, and told the car to ignore it. There was nothing connected to the outer passenger seat buckle at all, which surprised me. If I put a resistor back into the centre seat it throws an error saying it's not coded correctly since I've told it that it's not there.
 
OP
F

frogdr1ver

Member
Joined
Aug 27, 2021
Messages
11
Reaction score
2
Your Mercedes
Vito W639 2011
  • Thread Starter
  • Thread starter
  • #4
Thought I'd update this, having stuck my hand all the way up behind the glove box and not finding anything airbag like there. I looked on the passenger dash and all it says is Vito, not airbag or SRS. So there is no passenger airbag fitted. Which makes sense now as the connector on the centre seat would have been for the pre-tensioner, I assume there is one fitted to the passenger reae in the b pillar, and I assume it will for if the reel is rolled out.
 


Welwyn Merx Limited is a family run business with genuine passion, dedication and 25 years of experience dealing with Mercedes-Benz and AMG passenger cars.
Tel: 01707 395999www.welwynmerx.uk
Top Bottom