P1804 Clutch actuator thermal protection activated

Hi everyone,

It seems I also got lucky with my C3 Sensodrive gearbox. After a few miles (4-6), when stopped at 0mph, AUTO and snowflake start flashing together with 3 beeps. While this is happening, the car will not start in 1st gear or R. After about 15-20 seconds everything gets back to normal, and once moving the gearbox seems to be working perfectly, until next 0mph stop. Also about 2 weeks ago the "AUTO" button stopped working, so now the gearbox is in AUTO (or nor) randomly.

I did a Lexia scan and the errors are: P1804 - Clutch actuator thermal protection activated and P1705 (something related TCM voltage, did not save that one).

Did anyone got this issue fixed somehow? I went to a few garages and not a single one was able to point out what could be issue (including Citroen Garage).

IonutA wrote: ↑Fri Jun 21, 2019 8:39 am I did a Lexia scan and the errors are: P1804 - Clutch actuator thermal protection activated and P1705 (something related TCM voltage, did not save that one).

Hello IonutA

I would get it back on lexia and use it to the full potential of the machine.

Read the errors, note them with screen shots, run the car, observe the error condition and then a final lexia scan with screenshots of the code and description to get the latest faults.

Then you can also use lexia to diagnose the problem itself by looking at the thermal properties of the clutch actuator and the associated live data.

Your TCM voltage may well be connected to the Clutch thermal protection fault and without all the information, it will be difficult to make a diagnosis.

Hello C3driver52,

Thanks for you quick reply! The only pictures I have are attached to this post. The P1705 picture did not reappear after clearing them, therefore I have no picture with it.

BTW, the Citroen Official Garage did not recommend replacing any parts for the P1804 error since in their opinion this is not a defect. They recommended to avoid driving in heavy traffic and maybe change the gearbox oil.

Thanks,

IonutA wrote: ↑Fri Jun 21, 2019 11:16 am Thanks for you quick reply! The only pictures I have are attached to this post. The P1705 picture did not reappear after clearing them, therefore I have no picture with it.

You also have 'Gear lever signal fault, signal incorrect' as a temporary fault. With these temporary and intermittent faults it may be worth getting your own lexia setup that can be called into action if it happens again. It would be useful to gather more information on how often this happens and maybe even some live data if you wanted to dig a bit deeper into the fault.

IonutA wrote: ↑Fri Jun 21, 2019 11:16 am BTW, the Citroen Official Garage did not recommend replacing any parts for the P1804 error since in their opinion this is not a defect.

Well, I suppose that would depend on how often and when it happens. Once in exceptional circumstances is to be expected.

IonutA wrote: ↑Fri Jun 21, 2019 11:16 am They recommended to avoid driving in heavy traffic and maybe change the gearbox oil.

This is a bit silly. A car that won't drive in heavy traffic is obviously not right. There is a fault here.

Changing the gearbox oil is good advice, you can tell quite a lot about the internal state of a gearbox by the oil that is drained out. If you do this yourself, you can save the drained oil. Compare this in colour to fresh C3 sensodrive gearbox oil (here), smell, texture. Take photographs to compare new and old.

But the gear change solenoid is not lubricated by gear oil, so changing gear oil probably won't fix any defect in the solenoid department.

As I mentioned in the first post, the P1804 occurs after about 4-6 miles, so is not that seldom. I will change the gearbox oil next week and maybe also give a try lubricating the actuator.

I continued to investigate using a friend's Lexia (after some updates it's in French now ). It seems the error is marked as temporary while the engine coolant is below 93 degrees, but above that is marked as permanent and cannot be cleared. Below 92 no error at all. Also with the engine off the temperature sensor seems to indicate fluctuations, so today I'm having it replaced. Will keep you updated.

IonutA wrote: ↑Tue Jun 25, 2019 6:40 am I continued to investigate using a friend's Lexia

Hi

Lexia is very helpful, even if it is in French

IonutA wrote: ↑Tue Jun 25, 2019 6:40 am Also with the engine off the temperature sensor seems to indicate fluctuations, so today I'm having it replaced

So that would be a new clutch actuator?

IonutA wrote: ↑Tue Jun 25, 2019 6:40 am Will keep you updated.

Thank you

Just replaced the coolant temperature sensor, the issue still persists. Apparently the clutch actuator should not be replaced (at least for now) since the error appears even if the car is not moved at all ( start the engine when cold, left on N until it gets hot, the thermal protection error appears). Next week I'm going to another garage.

IonutA wrote: ↑Tue Jun 25, 2019 2:32 pm Just replaced the coolant temperature sensor, the issue still persists.

You don't have a coolant temperature sensor fault. So that is not a surprise.

IonutA wrote: ↑Tue Jun 25, 2019 2:32 pm Apparently the clutch actuator should not be replaced

Why not? Have you found the location of the clutch actuator temperature sensor? My best guess would be inside the clutch actuator unit.

The signal would go to the gearbox ECU, so there is a sensor, the wiring loom and its connectors and the gearbox ECU that play a part.

IonutA wrote: ↑Tue Jun 25, 2019 2:32 pm since the error appears even if the car is not moved at all

I don't quite see how this is relevant.

IonutA wrote: ↑Tue Jun 25, 2019 2:32 pm Next week I'm going to another garage.

Keep the P1804 thread update please

Hi there,

For the moment that issue got fixed by replacing the clutch kit, together with some adaptations of the clutch actuator. Apparently also the actuator has some adjustments that can be done, so now the car is running fine.

Sorry for the very late reply, I got my VPN out of service for some time and the access to the forum is banned from my country