Peugeot 406 HDI 90 brakehorse Turbo Diesel The temperature gauge falls back to zero and the warning light comes on. After a few seconds the temperature gauge rises to temperature and the light goes out. Assume it's the temperature sensor. Is it difficult to change sensor? and were is it?

I hate to rain on your parade but welcome to the world of French car electrics. You could try an owners forum or a non franchised specialist may help. This is why people in the know only buy new and sell on after 3 years. Renault, Peugeot, Citroen all suffer from nightmare electrical faults. My only suggestion is to check as best as you can all harness connections for tight fit and any corrosion.

I am sorry but we have no way to cross reference that information, contact the MB dealer parts dept to verify, but off the top of my head i would say no, the Germans would not make it that easy.

have heating in my peugeot 406 hdi when car is ticking over but when i drive for few mins the heater goes cold

The ignition key may be defective or in need of a battery to generate the code needed to disarm the immobilizer. Hope this helps!

temperature sender unit top of engine cylinder head make sure its okay
and make sure wire going to it is not grounding
if it grounds or earths it will send the gauge up and down

sounds like a fault on traction control or abs
check the abs rings on the front drive shafts

switch has broke inside itself

it will be your low volume pump in the tank

Yes i think that i can help you.Please just send me yuor car chassis number and mor details about the symptom

lift the carpet at o/s/f {drivers front footwell} there is two multiblock connecters guarenteed tobe sodden with water disconnect connectors& dry with a hair dryer on low setting hopefully the pins are not corroded reconnect connectors this is aknown fault i have worked with peugeot&citroen for 24 years kind regards alastair