Hello all - thank you in advance for helping with this.

Yesterday while out driving my SRS warning light came on. The car is an '06 Vantage 6spd with ~33k miles which I drive regularly.

I ordered a Foxwell NT624Elite code reader and pulled down a P0049 code - "Passenger lap belt pretensioner squib resistance too high"
I reset the code several times but it comes right back.

My car is a normal LHD US-market car. I understand that these code readers sometimes mislead with passenger/driver because of RHD / LHD confusion, so I also pulled the relevant live sensor data using the Foxwell:

Right side airbag squib : 2.52 ohm
Left side airbag squib : 0 ohm
Passenger shoulder belt pretensioner squib : 2.64 ohm
Driver shoulder belt pretensioner squib : 2.24 ohm
Driver airbag squib stage 1 : 3 ohm
Driver airbag squib stage 2 : 3 ohm
Passenger airbag squib stage 1 : 0 ohm
Passenger airbag squib stage 2 : 0 ohm

I moved both seats forward and back, and pulled on wiring under both seats and none of the readings fluctuated - so no clues there.

I believe what these readings are telling me is:

• The fault is actually on the Left (driver) side
• Most likely this is a loose / bad connection, given the 0 ohm readings
• The fault is in the Airbag wiring in or under the seat - not the pre-tensioner in the rear quarter panel

Do I have that right?

Thanks to all in advance for any guidance here.

Pics below for anyone who's curious about what this all looks like on the Foxwell scanner. It's not an AMDS, but it's pretty good.

 

Something's wrong here. a P0049 is an emissions code for supercharger/turbo overspooling. P-codes cannot describe an SRS issue.

An SRS issue would have to be a B-Code as it comes from the body control module where SRS is managed. A B0061 is an SRS generic code for a driver's side belt tensioner issue passenger's side a B0070.

https://www.safetyrestore.com/conten...eset-dtc-codes

Could be the foxwell you have. Sometimes these cannot read B-Codes, C-Codes or U-codes, just P-codes and/or can give some funny readouts even then.

 

I also noted there is an overlap with OBD codes.
In my research, I found this Aston Martin technical bulletin listing the SRS / RCM computer codes, and code 0049 does correspond to what the Foxwell is showing. I suspect the prefix character may be off.
https://static.nhtsa.gov/odi/tsbs/20...42192-9999.pdf

 

Yes, it has to be an issue of a prefix error if the Foxwell reported a P-code instead of a B-code. But especially a P-0xxx code as all P-0xxx codes are preassigned by the OBDII protocol and all manufacturers must use these as defined by OBD. Manufacturers can assign unique P-codes once they're into P-1xxx, P-2xxx, e.g., but often when one mfgr has assigned a P-1xxx definition, another mfgr will just use that one for the same system rather than assigning a new number for the same.

Also, the only faults that produce a check engine light are P-codes (power train faults). All others (B, C, U, codes) are either not shown anywhere w/o a scan, or are reported through messaging, or other failure lights such as SRS in this case.

 

My airbag light is on (2007 V8V cabriolet). When I hook up a scanner with live data, it shows 'right side airbag squib 0.52 ohms'. I believe it should be around 2.2 ohms like the others. Where is the right side airbag squib? Is that in the dashboard or the seat?
Incidentally, the error code relates to the passenger seatbelt pretensioner squib, which I sent to Safety Restore and they told me it was fine and didn't need replacing. But live data points to the right side airbag squib? I am confused.

 

Well, after analyzing the live data, I tracked down the issue to the passenger seat airbag. I removed the seat and measured the resistance of the airbag and it shows as 0.5 ohms, below the minimum limit. I bridged the connector plug with a 2.2 ohm resistor and the airbag light went out and all the codes cleared. Therefore my Autel scanner is mis-diagnosing the seat airbag as the seatbelt pretensioner. I need to contact Autel and also locate a passenger seat bolster airbag. They seem to be hard to find.

 

Hello,

Did you manage to identify the problem with your airbag? I have exactly the same fault with my 06 Vantage V8.

 

My passenger seat airbag is bad, needs replacing. The Autel misdiagnosed the DTC, but the live data from the Autel was correct. If you are getting the same codes, test it by unbolting the seat, disconnecting the battery then measuring the resistance across the pins of the airbag connector under the seat. Takes about 45 mins from start to finish.

I found scuderia car parts online that supplied a new airbag for about $400 with shipping and taxes.

 

Good Morning, did you ever find the issue. My car is doing the exact same thing.
Thankyou

 

That's likely a connector problem under the passenger seat. You could try to isolate it by installing a resistor across the airbag connector wires and see if the live data picks up the resistance. If so, then the vehicle and harness is good and you will need to measure the airbag resistance.

 

I’ve already fitted a 2.2ohms resistor and it didn’t change anything or fix it

 

Then you need to trace the short back towards the SRS module.