STOP! Engine Temperature Fault- Car's not overheating

[Tasmin200]

I've had a number of electrical issues on my 2010 207 1.6 Vti Automatic recently. The main ones being an ABS, power steering and speedo issue which I traced to a burnt out fuse box at plug 28V MR

I replaced the fuse box (same part number) and the 28V MR connector (soldered the wires) and this has solved the ABS issue however I now have this Problem 10 seconds after I start the engine and the cooling fan also comes on:

I assume this is connected to the 28V MR plug? Does anyone know which pin is related to the temperature sensor or suggest where I start looking?

Thanks, I hope someone can help.

[mickthemaverick]

If you get no responses you may be able to find the diagram at this site:

[PaulC5]

Could be the coolant temperature sensor is faulty. Plug in a code reader that does live data and see what temperature it is suggesting. Also check its connector/wiring, it may have been disturbed when you replaced the fuse box.

[Tasmin200]

I have now carried out the following checks:

-Replaced the thermostat and sensors

-Checked every wiring connector between the thermostat and ECU

-Checked continuity between the thermostat and ECU

-Checked the voltage at the thermostat end and got 3.3v which is correct

-Checked the radiator relay unit

-Carried out several bsi resets

I've removed the two earth connectors near the fuse box and cleaned them up.

I'm not getting any temperature related codes on my reader and the live data looked ok

I just can't think of anything else that could be wrong. Getting pretty close to giving up.

[PaulC5]

What temperature is the coolant sensor showing ? If you unplug it what does it then show and with the engine running does it again give the stop message and run the fan ?

We had a 2010 C3 with the 1.4 vti engine and that started running the fan when not needed. It turned out there was a known fault and Citroen's technical fix was to install a second temperature sensor on the thermostat housing in place of the bleed screw along with a short wiring loom. The old sensor was left in place but not connected. No idea if this would apply to your car though.

[Tasmin200]

I’ve come to the conclusion that the replacement fuse box I bought is faulty. I put the old one back in and obviously had the original ABS/Steering problem but no overheating message. I’ll try another one and let you know.