406 stop alert

A fault has developed on my 406 hdi that makes the STOP light flash and
the beeper to sound whenever the a/c is switched on. Also a message
appears"Engine temperature too high". This can happen even when the
engine is cold. The temperature sensor has been changed but this makes
no difference. Any ideas as to what is wrong?

 

behind the grille, there is a triangularish box,
inside there's 3 relay's, the downside one is faulty or has one of the
leads rotten off

good luck

marc

 

Thanks for that. Do you mean the long plastic box and the lowest relay
in it? I will let you know how I get on.
Tony

 

yup the very one

the sympthom you discribe varies from ECU to ECU, sagem warns
different than the bosch ones. but ten to one this is the fault

take a very close look at the wires and check for corrosion etc.

good luck

Marc

 

Hi Marc,
The fault was actually a defective low speed fan resistor which has
been replaced and all OK now. The relays were not at fault. Thanks for
your help.
Tony

 

This STOP light/temp warning light problem has plagued my '95 405, with or
without the a/c, and sometimes even when the engine is stone cold. But it
went away last year. And now it's back. Could the solution be the same?

And does this other solution from Tony also apply to a 405GL:

 

Tim
I don't think the 405 uses the resistors to alter the speed of the twin
fans. Instead the fans are either connected in series or parallel by the 3
fan relays behind the radiator grill. I should first check these three
relays then the associated wiring that often goes O/C due to corrosion, then
the fans themselves that should work when 12 v is applied.
Mike

 

Thanks for that Marc.
My 406 Hdi has just started doing the 'flash the STOP light once a
second' and the Air Con not working properly. Sure enough it was a
corroded and detached coil feed wire to the bottom relay in the
triangular box.

All fixed now.

Thanks again