I have had an unexpected warning light event occur after I changed tires/rims this past weekend after a track day. The TPMS light was on as usual, since my track rims have no sensors. Street tires/rims (with sensors) were re-installed, using a floor jack, one corner at a time; proper lifting points used.

I backed out of the garage without wearing my seat belt, so I had a the warning indication for that violation. When I restarted the Vantage to go back in the garage after completing the swap, the SRS/airbag warning light was on! I have done this exchange at least 8 times in the past without incident!

I have since gone out for a test drive and the TPMS light went out as normal, once communication with the sensors was re-established. Three start/stop cycles has not cleared the SRS fault...does anyone have any clue to what may have triggered the SRS fault? I've moved both seats as well, just for grins.

It appears that a trip to the dealer will be required to clear/reset?

 

That has to be coincidental, perhaps while jacking the car and setting it back down, it was just enough to interrupt an electrical connection to your SRS unit, certainly the wheels/tires themselves don't work on the SRS circuit, the TPMS sensors are radio-activated.

Some of the better OBD2 scanners can do SRS codes (European airbag module required) such as Acton brands and the like. Most don't list Aston Martin, but since the car is mostly Volvo electronics I just use that on my scanner and it seems to work fine in clearing codes and diagnostics. Yeah, I know - putting in VOLVO is a hack...lol

 

if you have memory seats, 9/10 it's the OCS sensor in the pass seat lower rails, just needs to be reset..do you have the memory function on the seat switchs??

 

Yes, the car has the memory seat function. How is the OCS (occupancy?) sensor reset? Is it reset via OBD II scanner or trip to dealer? Or some other "work around"?

Thanks for the information!

 

The OCS is reset by the dealer..believe its a module from Recaro..don't know if it's sourced by Volvo though..could be..If you can find a scanner that can read AirBag codes from Volvo..it's worth a try..but a dealer reset takes not even 30 seconds with are AMDS machine

But the fault is logged because the memory seats have lost there programming and clashed with the trimming behind the seat..this forces pressure onto the front OCS sensors and then has no pressure/weight on the rear sensors. There are 4 OCS weight sensors, 1 on each corner of the pass seat rail.

Good way to know if the seat has lost programming, power the lower cushion all the way back,.. then power the backrest backwards, if the lower seat cushion inchs forward to avoid clashing the backrest with the trimming behind the seat..then seat is calibrated, if it doesn't and clashes with the rear seat trimming, you just found your issue as to why the OCS needs to be reset...seats will need to be calibrated and THEN have the OCS reset..

Do the seat test and let me know if there programmed..do this for both seats..I can guide you to calibrate them..just dealer trip for OCS will be required to get the light out

 

Irish, you should write a book on all these tech tips for Aston's, who is EVER going to figure this stuff out otherwise??? Seat de-programming clashes with the SRS airbag light. <tsk> That's some crazy stuff and these cars have some truly weird workarounds...for example, it would not surprise me if say the following were true:

Owner: "My radio reception suddenly went from excellent to very poor, all I get is static now on the FM band."

Solution: "That's caused by the tire TPS sensor sending a radio wave to the module but it bounced off the oil reservoir cap because the car was taking a fast corner at the time of the TPS frenquency update, causing a shift angle in the geometry just enough to catch that wave and interrupt the FM antenna."

It wouldn't even surprise me.

 

This is a great idea. I'd buy one for certain

 

As usual, I believe Irish is right on the money.

My better-half likes to sit so upright in the passenger seat that it looks awkward compared to the driver seat when the cabin is not occupied. It also makes it harder for other passengers to get into the car, so I've made it a habit to recline the seat further when she's not riding with me.

One day I had my big bulky camera on the passenger seat and I had reclined the seat further back, and when I started the car I got the SRS warning. I was on my way to the dealer, so I asked my tech about it and he said to not recline the seat so far back that the back of the seat touches the trim behind it.

I don't have memory seats, so moving the seat back and then reclining it does not move the seat forward automatically again. This means that it is quite easy to recline the seat too far back to where the backrest touches the rear trim. This combined with the weight of my camera seemed to have tripped the warning. Sure enough, I tilted the backrest a little more upright and the SRS warning went away.

 

Who told you about the car I'm working on right now??

 

I checked the seats last night and both have lost their position programming!
I would be very appreciative if you could provide the suggested "calibration instructions"

Thanks again!

 

1) Power the seat fully forward. While the seat is in motion press the vehicle Battery
Disconnect Switch (BDS) to cut power to the seat. Reconnect (BDS) battery
power. The seat should now be in calibration mode.

2) Next recalibrate the seat as follows:
- Power the seat fully forward and hold the switch on for 4 seconds
- Power the seat rear height adjust fully up and hold the switch on for 4 seconds
- Power the seat front height adjust fully up and hold the switch on for 4
seconds
- Power the seat tilt fully forward and hold the switch on for 4 seconds
- Leave the seat for a 1 minute before adjusting the seat position
- The seat is now fully re-calibrated

****

You might loose window calibration..by using disconnect switch...

1)Hold switch to power drivers window down, keep holding switch for 3 seconds.
2)Hold switch to power drivers window closed, keep holding switch for 3 seconds, release switch and hold switch up again for 3 seconds. Open drivers door, window should lower to open door, close door, window should close to contact seal...window has been programmed. If window does not close when closing door, repeat calibration until successfull
3)Repeat steps 1+2 for the passenger window from either switch pack(not important) and test door open/close..

 

Thanks Irish!
I may have to grow a "long third arm" to reach the BDS in the trunk while I'm moving each of the seats forward, while waiting for the full moon to rise over my right shoulder for all the "magic" to work properly

I figured I would have to redo the window adjustments, and I'll probably have to reset the radio presets as well...

Thanks again!

 

The radio won't lose the settings..it should keep it in memory.

Some ppl do this procedure by disconnecting the battery..for us techs it's ok because we can save and restore the ECM's misfire corrections..but without a AMDS..you would be clearing the misfire factors and need to do the looong step by step road test to complete a misfire correction drive cycle..with these setting cleared, vehicle would not detect a misfire even if you had open secondary winding in a coil..a V8V would be running on 7cyl and no check engine light..anyone with a V12, same thing goes for DB9/S..etc

 

Sorry for resurrecting an old thread, but I though the solution would be of interest. The seat recalibration instructions provided by irish07 worked fine, but I still had the warning light.
I recently purchased a "European" scanner with SRS capabilities, which identified the problem as "passenger seat side air bag" resistance value out of range, which I interpreted as a wiring issue. Despite efforts, I could not clear the warning light.
Fast forward a few weeks to the Jan. 19th AMOC track day at Thunderhill. Los Gatos AM brought two Astons for test drives, their portable AMDS laptop and their very capable tech Darryl. The AMDS identified the "driver seat side airbag" as the problem. He then configured the scanner to display four resistance values from both seats and then he proceeded to "tug and pull" on various connectors under the driver seat while I watched the offending resistance value. We were able to quickly locate the offending plug/connector (the two wire connector to the left of the multi-pin) and obtain a correct and stable resistance value. He then cleared the offending code and the SRS warning light has not been on since .

I have learned up a couple of important lessons from this experience:

• My "European" scanner is apparently for RHD vehicles, so passenger means driver here in the US. Much time lost looking in the wrong places.
• Darryl informed me that a single component fault anywhere in the SRS deactivates the entire system, not just the offending air-bag-I've been driving around for months with an inoperative safety system.
• In an attempt not to duplicate the event that caused the problem in the first place, I now use two floor jacks to raise the car evenly front to back, which in reality reduces the time needed to swap tires.

Thanks again to Los Gatos AM, Darryl and to irish07 for their help-it is very much appreciated!

 

The scanner is good that have but the car is setup in RHD software for interior electrics, the AMDS pids detect that it's a LHD vehicle and changes the pids to show correctly so the tech does not misdiagnose..are old diag tool WDS doesn't do the conversion for you so like it scanner "RH pretensioner = LH pretensioner"....etc

Meet Darryl last month in Vegas at a conference..him and Robbie are real good techs for Los Gatos