V6 Coupe Cooling Fan Switch

[Daviewonder 533 3 Cars]

Hello, went shopping earlier in the coupe and the stop light on the dash came on due to the fan not cutting in. I've had a quick looksie but I'm not sure where the fan switch is, anyone know?

 

Cheers

[welshpug 1,666]

in a 406 V6?

[Daviewonder 533 3 Cars]

Yeah Mate sorry, 406 coupe V6

[welshpug 1,666]

they don't have one as such, they use the brown Bitron sensor that's in the water housing just under the throttle body.

 

there's a control box under the left hand wheel arch liner behind the fog lamp, bolted to the inner wing.

 

and there's 3 relays in the middle of the fan cowling behind the grille.

 

to see if the relays and control box work, just unplug the sensor, the fans should come on full as a failsafe, IIRC with the a/c on one or both fans should be turning at low speed constantly.

[Daviewonder 533 3 Cars]

Sounds a bit more complicated than the 205 set up

 

I'll have a go at unplugging the sensor then mate, see what happens.

 

cheers

[Daviewonder 533 3 Cars]

Ok here's the story so far- I carried out a few checks and found both fans to be faulty so I bought two new fans and fitted them and replaced the antifreeze and bled the system. When I ran the car up the fans work ok and cut in but didn't seem to cut out again, I had been checking how hot the hoses got and they all got hot apart from the bottom one also the rad didn't seem to get hot either. I had the car running for about 40 minutes and it didn't overheat, I'm stumped on this, any ideas? I thought it might be the thermostat not opening but would this explain the cold rad?

 

cheers, Dave

[Daviewonder 533 3 Cars]

Went out for a test run in the car today after bleeding a small amount of air from the system, had to pull into a car park due to the temperature going right up to over 100, it's the same - cooling fans cut in, hot top hose, cold rad and cold bottom hose. I think it might be the thermostat but would the top hose get hot if the thermostat wasn't opening?

 

Please help

[welshpug 1,666]

IIRC the thermostat feeds the lower pipe.