2013 DB9 TPMS puzzler

[TBM850]

Hello all,

I've tried troubleshooting this to the limit of my capabilities. I wonder if any of the knowledgeable folks on here might have some suggestions.

2013 DB9 LHD

TPMS consistently faults after being parked up last winter.

3 good sensors. Only the passenger side rear wheel sensor consistently cannot be detected.

I replaced all four sensors with new. No luck.

Replaced the wheel arch TMPS antenna with a serviceable one. No luck.

Took out the TPMS ECU and cleaned the connector pins. No luck.

The ECU seems to be doing its job and is detecting the same three wheels that didn't have a fault before, so I doubt that is the issue. New antenna and wheel sensor addressed those possibilities.

I am beginning to think I have a broken wire in the circuit for the passenger side rear wheel TPMS sensor.

Where does the harness route after it leaves the TPMS ECU? How would I test it?

I did have some minor mouse damage on the firewall ground wires that are directly behind the engine bay fusebox. I believe that I did repair all those but does the TPMS have any wiring in that area?

Any suggestions would be greatly appreciated.

Cheers

Paul

[EVR]

I have developed a very good knowledge of these sensors and the logic back when I had my 2011 Vantage N420.

Only thing that comes to mind, is the sensor batteries are on their way out.

Check these threads of mine: you should have the latest Beru/Huf type like me, so it should be somewhat simple to change and synch them.

https://www.pistonheads.com/gassing/topic.asp?h=0&...

https://www.pistonheads.com/gassing/topic.asp?h=0&...

[Greathey]

Just do like many people here and buy a delete kit

https://astoninstallations.com/product/tpms-defeat...

[Simpo Two]

Greathey said:

Just do like many people here and buy a delete kit

https://astoninstallations.com/product/tpms-defeat...

But - it says 'The Smartire system was then replaced sometime in 2010 with the Beru system. This TPMS defeat cable will only work with the Smartire system.' The OP has a 2013 car.

[TBM850]

Thanks for the replies.

The DTC faults are C172A93 "No communication with the right rear trigger" and C173887 / C173786 Can bus data errors.

I've swapped out the trigger module and the fault stays there so it has to be wiring.

Does anyone know what the readings should be on the pins in the trigger connector? If I recall there are only four pins.

Likely 12V PWR, GND, TX, RX?

Appreciate the help on this puzzler!

Paul

[TBM850]

To follow up on this fix. It actually was a broken wire leading to the TPMS trigger antenna. The Gemini AI advice on this was actually pretty solid to be fair. When the sensors, antenna and ECU have been eliminated as culprits it might be time to start tugging on wires. I was lucky and my broken wire was 6 inches from the antenna. Easy fix but a lot of tail chasing before the real culprit was identified. Apparently wires for the TPMS trigger antenna do commonly break where they exit the boot to the rear wheels.

[AM4884]

Well done finding the fault. +1 on using AI to help resolve faults. I've taken to describing the situation and asking for advice. Shockingly good results and has led me to a couple of "non-obvious" solutions that weren't resolvable by swapping parts or testing functions.

[TBM850]

Thank you! Yes, note to self that AI and eBay are super resources these days. I've found so many Aston parts for 1/3 of the price on eBay. No tariffs or extortionate DHL shipping from the UK.