I have an airbag Flash Code 17 with DTC B2291 ( PID 24 ) which calls out Passenger OPS Sensor 4 ( outer headliner/B pillar) - Sensor fault. I intend to clean and reseat all connectors, however I am curious if the A pillar and B pillar sensors are the same and if they are interchangeable. I am considering swapping the sensors, resetting the RCM and see if the fault follows the sensor. My RCM was recently cleared of all crash codes, and I've tested and confirmed it senses all belt pretensioners and airbag DTC's function properly and using AE ST-06. I am able to reset the RCM for each specific condition tested ( currently using two 3 OHM resistors in place of two stage driver airbag squib and 2.6 OHM resistors in place of all belt pretensioner squibs as a debugging method). I want to fix the OPS fault, while I am searching for a driver airbag. The belt pretensioners are in the shop being rebuilt now.
I see in the SRS DTC PID TSB that the OPS can surface a 17 - B2291 - PID(28) which indicates Passenger OPS Calibration fault with Possible Cause: clear fault codes and cycle ignition... this tells me the OPS system is capable of recalibrating itself and I would venture a guess the OSM has the algorithm to perform such a recalibration and that all four of spatial sensors are just off-the-shelf ultrasonic transducers each with the same characteristics and perhaps the same part number. I can't find the part numbers on the web and I haven't taken the B pillar trim off to look at the sensor.
Here is an interesting paper written by David Breed from ATI who worked for one of the companies that helped bring OPS to the XK in 2001.
http://www-nrd.nhtsa.dot.gov/pdf/Esv/esv16/98S5O13.PDF
Figure 1. in the paper depicts the same OPS that's in my 06 XJ8.
Thanks, Bob