Hello NAM! I recently purchased my second R53, and so far I'm loving it. I'm chasing a couple warning lights down at the moment. One is a evap leak, getting it smoked next week to try and find it, so I'm not too worried about that one yet.

The issue I'd like a little help with from NAM is the SRS light. I'm showing a code 81 on my scanner. I'm not sure where this sensor is located. I've pulled the trim off the interior, and the sensor at the base of the left hand B-pillar is in place and appears to be in good condition. Is there another sensor located elsewhere? One in the door? Or is the sensor in the base of the B-pillar the only side impact sensor?

 

There's another set of sensors inside the doors. Interestingly, they're pressure sensors. When the door gets smashed in quickly there's a pressure wave of air that's detected by these sensors.

Also, there's no way you can tell a sensor is good just by looking at it so I wouldn't rule out the one by the B-pillar. You'll have to test them.

 

I'll check into the door sensors.

What's the test procedure for them?

 

Try swapping the sensor left-to-right and see if the code changes.

 

Well, I decided to try swapping the door sensors around today, while I was replacing my window regulator, and I ran into a small issue: I can't seem to find them. I followed the wiring from the door connector to each termination, but I didn't find a sensor at the end of any of them... Build date 07/05/04, what are the odds I don't have those sensors and instead only the sensors under the B-pillars?

 

Behind left side rear seat, S71 part.

 

Wow, that's an excellent resource, thank you! I'll swap those sensors today and see if the problem follows the sensor.

Just to verify, it's possible that I don't have the door pressure sensors that were mentioned by another poster above?

 

Bumping this. Replaced the left hand sensor under the B-pillar with a new sensor, checked wiring and connector, still having the issue.

Can anyone give me more information on the door pressure sensor?

 

So I've located this page in the service manual. Problem is, I don't appear to have the part labeled "B78" or "B14143".

Where it gets weirder, though, is the I don't have those sensors on EITHER front door(even though I'm only throwing a code for the driver's side), and I don't appear to have any wiring that could go to them. Like, there's no unplugged connectors or cut wires in the door loom that I can find. Somebody help me out here, I'm losing my mind.

 

I'm dumb. My car is apparently MRS4, not MRS5, so I haven't got door pressure sensors, if I'm understanding this correctly. So that leads me back to the sensor under the B-pillar, or, more likely, the wiring, since swapping the sensor didn't do anything.

 

Can use wiring from this doc, page 132.

 

I keep getting errors trying to extract that, any chance you've got a non-compressed version?

 

try this

https://mega.nz/file/BM8EhaTK#g6tT0B...aQuexnQB7XVco8