I may be old school here, but I find TPMS to be an annoying unnecessary device. I'm getting an intermittent "Tire Pressure Monitoring System Fault" error and while I'm tempted to go digging around for the antennas, and the module or trying to identify the tire with a problem sensor, there's a part of me that just wants to disable the stupid thing altogether.

Everything I've read about the TPMS says the system is temperamental and that one can spend a lot of time and money replacing just about every component without success.

Ok, all that said:

1. Do I have to go to a jag dealer for a TMPS sensor reader that can tell me if any specific tire sensor is failing?
2. Has anyone disabled the TPMS?
   1. Uh, is this legal in the US
3. I read the module is susceptible to wire abrasion. How easy is it to get to? Do you really need to pull the front bumper off?

Many thanks!

 

Any tire dealer will check you sensors for free.
TPMS is required for a vehicle to be Sold New in the US. After the original sale, whatever goes. However, I dealer will NEVER disable due to liability.
Pull out the front-right headlight assembly and look down and forward to where the bumper attaches to the frame bracket. Sometimes the duct tape (yes) is in the wrong spot and the harness in that location gets chafed.

 

I also find the TPMS unneccessary but it is mandated here in the UK where disabling such 'safety' devices can have serious legal consequences.

The most likely cause of the fault message is a failing sensor battery and I'd eliminate this simplest possibility first before looking for initiator, sensor or harness faults.

I haven't replaced my sensors at approaching 8 years although some members have reported problems in as little as 5 years. My local tyre depot has checked the signals on mine at tyre changes and I presume tyre depots in the US will have similar meters to do this?

Graham

 

I'm hoping it's just a simple battery. I'll take it to a tire shop (as we call them here in the states...depot does sound more refined!)

I'd like to just be able to do this diagnosis all on my on. I'd like to get the the jaguar diagnostic / programming software or a good scanner. I might have to post on that!

 

You wouldn't think so if you saw one.

Graham

 

The plot thickens. Could this be the dreaded "you need to look under the front bumper for a wire bundle" issue ?



Where to start diagnosing this?

 

If the TPM sensors in your wheels are 8 to 10 (or more) years old, it's the sensors.
If you replaced the sensors with new (or good used) ones that you purchased on eBay or from Rock auto, it's probably still the sensors.
I have found the TPMS on Jaguars to be extremely reliable. Aside from squirrels eating the antenna wire (rear is exposed behind the splash shield) and low vehicle battery voltage, failures have always been the wheel sensors (or low tire pressure).
The initiating antennas themselves are nearly indestructible and are easily accessed behind the wheel well/splash shield.
The connectors at the antennas are sealed but could be affected by extended flooding in salt water. (Flood vehicle?)
The single receiving antenna is located behind the rear seat.
Wheel sensors contain batteries that are supposed to last +/- ten years.
The sensors have date codes that can be deciphered. If you purchase new sensors that are more than two years old, reject in favor of sensors with fresher batteries.

The simple solution is to visit a reliable shop/depot and have the sensors replaced. Explain your concern about sensor manufacture date and ask for confirmation of fresh modules.

best regards,
Bill

PS: The preceding was composed as you were in the process of posting your trouble code.
Remove the RF wheel and remove several fender-liner screws adjacent to the bumper and peel back the liner to expose the antenna and wire for inspection.
If all appears well, disconnect the antenna connector and check resistance to ground with ignition off.
Don't recall the exact values but compare RHS and LHS if the problem is not otherwise evident.

 

Have you actually got that chassis code?

The antennae are behind the wheelarch liners and the harness connectors are easily accessible from there:





Simple enough to check for grounding.

Graham

 

Hey Graham, yes I have that actual code. I pulled it today. Hopefully the short will be easy to find. I'm hoping I don't have to pull the headlight out to get to it.

 

After the easy check behind the fender liner, you may study the wiring diagram to see if the problem may be behind the rear seat or adjacent to the driver footwell.
The harness does pass through the left wheel well too. But, if you have to remove the bumper, it does get easier with practice!

best regards,
Bill

 

Hey! Maybe from Post #2 on this thread!!!

 

I'm so ashamed . In my defense. I was not expecting the initiator error to lead to the same spot under the headlight.

I should say I have access to a hydraulic lift. I can remove the splashguard or remove the headlight as mentioned in...uhhh....post#2 of this thread. I'm leery of messing with the headlights due to the whole self leveling / aiming bit...

 

I would fix or replace the TPMS. Should not be disabled IMO.

 

Removing the light pods is very easy -- refer to the maintenance manual for your model year. On mine, it's a couple of screws, a washer tube, and of course the electrical connector.
Short of dropping them and kicking them around the garage, you won't affect the light in any way by doing this. It'll do it's dance and realign when you plug it back in and start the car.
Open the back access port, where the light bulb is replaced. Examine the wiring. Some Hella lights of that era suffer from wire insulation falling off due to plastic degradation.
If you see flaking insulation, examine it very carefully(!!), and try not to disturb the wiring in any way. If basic cracking and some flaking, everything should be fine. Lots of flaking means you might have an internal wiring short.
If you have lots of flaking, you can pull them apart and rewire. Tough job, though.
Of course, no flaking, no problem.

 

I agree. The wheel sensor batteries fail after 8-10 years, though 2 of the four on my '07 are still good after 15 (maybe the PO replaced the rear ones?).

The OEM (in my model) is VDO, which are available for $50 - 60 online.

 

I replaced every module and every receiver, every initiator and did a pin-check. I reflashed all modules a few times.
My TPMS does not work.

 

I recall that episode, CeeJay. And because I’m stubborn, I’d probably be getting bitter about it and continue the fight, lol.
Unrelated?? I don’t tempt fate. I replace the sensors each time I replace tires. And not with knock offs.
CeeJay’s note above was accurate in my case. On removing the bumper I re-routed a few things that I thought would cause grief in the future. The TPMS wiring was one of them.

 

The "interesting" change for me @ tire shops around here is that they will not longer install TPMS sensors that I buy. They will only buy ones they provide. They will replace the OEM with OEM and add 100% mark up and that's not a typo. Said the the change was corporate policy. 3 tire shops near me and all said the same thing. I know this is common with most shops where they mark up parts and they used to install parts you bought but would not warranty the job. The TPMS thing would just be petty if they didn't literally double the price.

 

The nice thing for me is my son is a mechanic at a dealership (not Jaguar though)

We just checked all the tpms sensors and they’re fine.

we’re about to pull the front right headlight then the bumper if need be

 

Here are the connectors im seeing. I think the wires are supposed to be green and green and white.

I don’t see them though