TPMS Module Replacement


(Brett) #1

A few weeks back I was driving my car, and suddenly the dashboard gave a Check Tire Pressure warning on several of the tires. After checking the tire pressures with several gauges that are accurate, I found that my pressures were correct. This has been going on for the past few weeks where sometimes I’d get the warning on some or all of the tires, and sometimes everything would function fine.

There are apparently two possible causes of this. One is caused by the TPMS system needing a software update. The other is caused by a faulty TPMS module. Because only the dealer can do the software update and there’s no guarantee that doing the update would fix the problem, I decided I’d better just replace the TPMS module. If you decide this is something you need to do to your car, the steps to complete the task are below. Not sure if its the same on post-facelift cars.

Start by removing the right seat (passenger for those of us in the US). You’ll need an E12 external Torx bit to remove the four bolts holding the seat to the floor board.

The TPMS module is located under the seat. However, to get to it you’ll need to completely remove the seat from the car, so you’ll need to unbolt the seat belt too. It uses a T50 Torx bit. Unbolt the belt, pull the wire from the retainer, and disconnect the wire connector.

Also, you’ll need to disconnect the wiring harness that connects to the bottom of the seat. There should be three connectors. You only need to depress a tab on each to disconnect them.

The seat is very heavy and bulky, so you may need a helper to get it out the front door. Next, remove the front and rear scuff plates. They simply pry upwards which you can probably do with your hands. Also, with the scuff plates off, you’ll remove the B pillar cover. It also pops off. Pry the top loose, and then you should be able to lift upwards to free it from the bottom retainers. Pull the back edge of the front carpet away from the rear carpet. You should see this.

Your TPMS module is under the ductwork. There is a ductwork connection directly in front of the steel brace in the right of the picture. Wiggle the ductwork loose from the connection and then work it through the opening in the brace to remove it. Now you should have direct access to the TPMS module.

Just disconnect the two wiring connectors and remove the two 10mm nuts holding the module to the floor. Installation is the reverse of removal.

One thing to note is that once the new one is installed, my understanding is that you’ll need to to get the software uploaded to it. I went ahead and set up an appointment with my local dealer to have this done soon. So far, the dashboard has not had any pressure warnings, but that doesn’t mean its functioning properly yet. But at the very least, I’ve saved myself from paying the labor for installation.


(Gary Crosby 75 XJ6L, 85 XJ-S, 09 XF Supercharged.) #2

Brett,

Great right up. I have a question tho that hopefully you can answer. Do the sensors in the wheels use batteries? I assume they do…but maybe they have an inertia type piezo electric driver.

I would assume that there are two parts…the wheel senders and the TPMS receiver. Depending on the cars age…i would have gone for wheel sensors first…especially if sudden cold weather hit…which could impact battery performance…you don’t discuss the age of the car or if the wheels sensors had been replaced at some point. What caused you to suspect the TPMS module?

Cheers

Gary


(Pete55Tbird) #3

TPMS lite. Totally OFF THE WALL answer. On my 2011 Honda CRV I went through that. Finally took it to the
dealer since I had an extended warranty. Took it there TWICE, cost me $140 to find out the issue was
the adaptor I plugged into the car to charge my cell phone AND my GPS via USB ( two ports ) into
the cars plugin. That’s my story and I am sticking to it. Pete


(Brett) #4

Gary, I’m not 100% sure how they are powered, but I know the wheel sensors do have a finite life span and must be replaced after a while.

The reason I went with the module is for two reasons. First, I did some research, and it seemed that the module was the typical issue when this problem occurs. Secondly, the fact that it would go back and forth from the tire pressures being fine to being underinflated at random times makes me think its a communication error. Also, it wasn’t just one wheel tripping the warning, but some or usually all of them. And just as quickly, it would be fine again and I’d have no warning.

I guess the confirmation will come this Friday when I take the car to the dealership to have the software update done. If I’m still not getting any warning lights, then my suspicion was probably right.


(Brett) #5

Wanted to give everyone a quick update. I got the software update done at the dealer this morning and drove the car around for the rest of the day. The Check Tire Pressure warning didn’t come on once. Before the fix, it would have gone on and off at least a dozen times in that many miles. I feel pretty confident that my fix worked.