1991 "SERVICE LTPWS" LIGHT

[Coupe de jour]

My Service LTPWS light is lit on the DIC. I retreived F/C's 24(RR), 34(LR), and 54(RF). I always assumed I had three bad sensors and planned on replacing them when I got new tires.

Recently, I ran over some debris and cut the right rear tire which developed a slow leak. Eventually, the "Low Tire Pressure" light illuminated even though I was getting a fault for that sensor. When I went to get the tire replaced, I had the technician show me the rim before he mounted the new tire. It had the correct orange sensor designated for the right rear but I noticed it had a frequency printed on the sensor. Where these sensors available in different frequencies?

Since the system worked properly, I assumed the control unit was falsely reporting fault codes. I went to the dealer to order a new control unit ($145), but my parts guy told me there was a note in the computer that said the dealer only must disconnect the old circuit board and reconnect the new one.
Does anyone know why the dealer has to perform this operation? Seems like I should just be able to plug in a new control unit.

Thanks,
Kurt

 

[Seahorse51]

Mine does the same thing but only on the right front. Strangely enough, when I aired it out this weekend (150mph) for a couple miles the light went out. I came back on the next day. Strange. I guess I have to air it out more often.

 

[Coupe de jour]

I did some further checking and found that compared to the left front which had consistent readings, I could not get the same or consistent reading out of the right front. I disconnected the wiring harness from the motor and the SRC module and checked the continuity from one end to the other. No problems there.Does anyone know if there is a place that can check/repair the SRC module? The dealer wants $1700 for one. Seems kinda steep for one circuit board.

Thanks,
CDJ