2015 C4 B7 TPMS

[DHallworth]

Evening all,

Does anybody have any information relating to the TPMS system on a 2015 C4?

We've got a TPMS light on the dash on my wife's car but I can't get any comms with the TPMS module in Diagbox. I'm unsure if my Diagbox is too old to talk to it or if there is something wrong with the TPMS module. I can't find anything online and don't even know where the module is located on this car.

Would be grateful if anyone knows anything about the system.

Thanks,
David.

[mickthemaverick]

Granny to suck eggs comes to mind, but you have checked the pressures David I assume? You may glean something useful from this link, I haven't read it through myself!! https://erwinsalarda.com/the-ultimate-g ... rocedures/

[RichardW]

Do you know what system it is running? Later cars went to an indirect system that uses the wheel speeds - on our '17 Picasso with this type you get a warning (which doesn't actually say low tyre pressure...) and then it doesn't go off till you go through the re-set procedure. The '13 3008 has direct system, and this gives a warning of a specific tyre being low, and the light goes out when you pump the tyre up. I suspect that if the indirect type there will be no TPMS module - it is probably done via the ABS module. Is the outside temperature still reading OK?

[DHallworth]

Sorry for the lack of replies. I’ve been feeling a bit rough and haven’t been online much.

This car has a sensor in each wheel that monitors the pressure.

From memory, this one’s never told us a specific tyre has been soft. It’s only ever put a TPMS light on the dash along with the word “service”.

I’ve checked all the pressures on it several times and am absolutely confident that it’s not got a soft tyre.

At the moment I’m getting the TPMS light on the dash accompanied by the service light.

[DHallworth]

We had the C4 in to my friends garage this week to get the timing belt and water pump done on it. Whilst he had it I asked him to read the codes off it and see if he could find anything for the TPMS as we're still getting a warning light for it on the dash.

The same as with my Diagbox, he couldn't get any comms from the TPMS ECU so I'm now thinking that this could well be a TPMS ECU issue.

Does anybody know where the ECU for the TPMS is located on the car? I can't seem to find anything about this system anywhere

Thanks,
David.

[mickthemaverick]

As far as I know there is no separate ecu for the tpms. I believe the sensors are monitored by the BSI but I may be wrong. This site has some info about the system : https://erwinsalarda.com/the-ultimate-g ... rocedures/

[DHallworth]

If I look on eBay, there are listings for a TPMS module for it so I think this one is just before it moved to the BSI setup.

[KennyW]

David,

Does your TPMS module have a small battery within, if so it maybe that, but I don't know if its worth changing battery or module.

Probably easier changing module for new since it will require tyre to be removed from rim.

Best of luck

Kenny

[DHallworth]

If I’d lost one sensor or had a fault code visible then I’d agree about changing a sensor but for the module not to be showing at all during diagnostics is what’s throwing me.

[Paul-R]

My 2015 Peugeot 308 has passive TPMS which relies on detecting any discrepancy between wheel speeds from the four ABS sensors. It has the same/similar structure as the equivalent year C4 so maybe yours is the same and there's no ECU to be found?

[DHallworth]

This one definitely has sensors in each wheel. I’ve seen them when changing the tyres.

[DHallworth]

Bit of an update to this one...

My Lexia and Diagbox wouldn't take to the TPMS on this car. My friend who is a mechanic has a Snap-On and something else which wouldn't talk to it either. When going through the log on the dashboard, it told me that there was an error on all 4 TPMS sensors. Due to this, I'd assumed that the TPMS ECU had packed in.

I recently bought an Autel diagnostics unit and last night plugged the C4 in. Interestingly, the Autel communicated with the car perfectly and lo and behold, there was the TPMS ECU with 1 stored code.

When reading the code it pointed towards the rear right hand sensor being faulty.

I've ordered a new, genuine Citroen sensor. Now all I need to do is figure out how to "excite" the new sensor when it arrives.

David.

[DHallworth]

To close this out, I bought an Autel TPMS tool to sort this out.

I fitted the new TPMS sensor, opened up the new TPMS tool which read the codes of the 3 existing sensors and it excited and read the new sensor.

The tool then tells you to connect it to the car with the OBD cable that came with it. Once that was connected a few seconds later a green tick appeared on the screen.

The TPMS error has now disappeared from the car for the first time in a long time!

David.

[RichardW]

Odd that Diagbox wouldn't talk to it, but good work on getting it sorted!

[Paul-R]

What version of Diagbox is being used? Also, is the Actia VCI full chip? Either of these might be the reason.