dudeinaTL

iTrader: (1)

I've got a TPMS System Error. Is the dealership the only place I can go to determine which sensor is bad?

I know a general OBD scan won't cut it, and I fear a tire shop might have to dismount all tires & only rely on a visual inspection. Or am I wrong with this thinking?

Different dealerships are quoting widely varying costs & while I really don't have anything against dealerships, I try to do as much as I can myself & go to the dealer as a last resort. 08 TL-S.

dudeinaTL

iTrader: (1)

Alright I take my question back. The car itself tells you which sensor is bad.

A lot of threads that come up as results from a search on TPMS issues just tell you to see if any sensor reads 58psi, but if you are already at the System Function Error, all tires will read "--".

The key is to go into the Diagnostics menu (Info button). It lists all the issues the ECU has detected.

It'll read something like "Tire Pressure Monitoring: 32". You really don't know what that means until you have the voice read it out, then it tells you which tire it is. I had messages for all of mine in January (when I put on my winter set w/o TPMS). This allowed me to make a chart:

Tire Pressure Monitoring: 32 = Passenger Front
Tire Pressure Monitoring: 34 = Driver's Front
Tire Pressure Monitoring: 36 = Passenger Rear
Tire Pressure Monitoring: 38 = Driver's Rear
Tire Pressure Monitoring: 41 = Spare

These also show the dates they occurred - and they all were in January. However, one or more still had an issue, so basically I had to clear the ECU (Menu/Setup/Cancel hold, go into XM, look for ECU reset). Now going back into Info->Diagnostics, only one message persisted which told me that I had a bad #36 (Passenger Rear).

There you go...no need for a scan if you have a bad sensor. This might also help if you are unsure of your TPMS system state. Just for kicks I went to a small tire shop who went around & scanned each tire with a handheld device in close proximity to the stem. They reported that all 4 were bad. Funny thing is, the proof they provided was by scanning the Passenger Rear tire (which spit out the same value even after air was let out)...

/end thread...the older I get, the lazier I get with troubleshooting

paperboy42190

iTrader: (7)

there is no tpms sensor in the spare tire, so I highly doubt code 41 will ever pop up.

sensors are easy to replace. once the tire is off(any tire shop can do this), the sensor comes off with 1 nut, it'll take like 30 seconds to swap out, I've done it before. then proceed to mount the tire back on

dudeinaTL

iTrader: (1)

All 5 codes were present on my car (including 41). All of the 30-something codes indicated passenger/driver & rear/front, but 41 did not, so that 41 meant the spare was just a guess from process of elimination. Another guess is that 41 may just mean some general error, because it was present when I had my winter set on without TPMS, but maybe my wheels with TPMS were close enough in the garage that the system picked up a signal from one but couldn't accurately draw a system diagram.

I know a TPMS sensor is easy to replace, my issue was if I had to go to the dealership to figure out which one. My answer was that it's not necessary if you check the diagnostic info on the car first, and then, yes, you can go to a tire shop who might have a handheld device that can read the TPMS sensors.

rossv1

Bookmarked. I've got a bad one too and always wondered how they knew which one was bad without taking off every tire.

vietxquangstah

iTrader: (7)

There's a TPMS tool that you can hold against the tire on the sidewall near the valve stem and it will tell you if that corresponding sensor is working or not.

I don't know the name of the tool or how much it costs but I used it before a few years back.

muuppal

which TMPS sensor to buy? does replacing TMPS sensors requires programming them. checked few tire places, getting around $100 for each sensor replacement/programming.