Peugot fan

Please help ASAP as I am kind of stuck in Blackpool!!!

Weathers nice but I need to get home.

The car is a 406 2.1TD
The car has done 148k miles and is in reasonable condition.
The car is overheating, the fans at the front do not appear to come on.
I have swapped around the three fan relays at the front, that makes no
difference.
I have shorted across the coolant thermister switch with no joy either.
How do I test for a live feed, are there any common issues here?

Many thanks

 

As an addition, I have just shorted across the temperature sensor and
the fans do not come on, I also tested for correct voltage at the sensor
and it was ok, so the problem is somewhere between the switch and the
fans... ?

I have also had the headgasket professionally leak tested and the
cooling system, all are working just fine.

Andy

 

dreadly wrote in message

As a 'get you home method' why not just wire the fans to a ignition switched
supply so that are on all the time the engine is running?

Normal cooling is with the fans in series and high speed connects them in
parallel

 

Thats interesting, it means that if one of the fans gives up the ghost,
they both stop working does it???

I suppose I need to check the fans but the wirings all hidden and
strapped up with akward access.

I am going to check for broken wires tommorow.

Andy

 

If all else fails use the "on the road" emergency cooling - run the
heater full blast. You will get hot but the engine will cool.

 

The cooling fans on the 406 work in series at low speed either when the Air
con is switched on or temp reaches start value 90 deg C. High speed is
achieved by both working in parallel this starts at 118 deg C.
You can check the fans are working and that the fan fuses are good by
switching on and starting the engine. Then remove the brown plug on the
thermostat. This is the sensor that controls the fans via the bitrol
system.The other 2 sensors one controls the temp gauge and the other is
associated with the engine ECU. Both fans should come on. If only one you
will get cooling at 118 degrees upwards. There are 3 fuses for the cooling
system that are located by the battery housing under a cover the 2 fans each
have a 40 amp fuse.
I have been running on one fan for 4 years without any problem but don't get
caught up in traffic for a long time.
Over the weekend I had a look at the problem but find you cannot get at any
of the wiring beyond the control relays without removing the 2 rads and
intercooler. The fans are switched on using the 3 control relays by
switching an earth on to the appropriate relay from the bitrol control
system.
Good luck
Mike

 

If, as you say, unplugging the brown connector should cause both fans to
run, couldn't the original poster use this as a method of getting home from
Blackpool?

 

He could but I would not advise as he will have no further warning of
trouble as this will also cause the STOP light to illuminate and his
temperature gauge to read off scale.
Mike

 

Many thanks for the usefull reply, however, I am a bit new to peugeots
and I can see two 'brown' plugs.
One is underneath the Temperature sensor on the right hans side of the
engine.
The other brown connector is at the front right of the fuel filter housing?

Andy.

 

I have tried disconnecting all of the sensors and plugs I can find, none
make the fans come on! - I have checked the 40amp fuese, I cannot remove
them as they are heavily corroded, but they are not blown.

Does this have a bitrol sensor, I thought that was only the HDI ?

Andy

 

If the connections are heavily corroded, then they won't be working

 

I do not know the answer but, as Michael said the plug by the thermostat, I
guess that means the one by the temperature sensor rather than by the fuel
filter.

 

SNIP>>

Yes, I went out last night and disconected every single connector I
could find, none of them made any difference!

I am thinking of trying an auto electricians - *Defeat*

Andy

 

I know the feeling, but I suppose there is wisdom even in defeat ;o)
Let us know how it pans out.

 

It is booked into a french auto electrics specialist in Redmarsh estate,
Blackpool tommorow morning.

Watch this space!!

Andy

 

Update..

The problem is now fixed.

I took it to what I can only describe as the worst garage in the known
universe, the garage who where trying to sting me for a new ECU, so I
recovered the vehicle.

I drove back to Bournemouth at 02:30 in the morning to avoid the
traffic, foolishly taking the toll road thinking it would be a nice
straight run only to find one pay booth open and a big queue of traffic
all beeping there horns at somebody who had forgoton there money.

I got a local chap I know (auto electrician of 25yrs) to take a look and
he traced the fault to the Bitron device under the front left wing.
Upon further investigation the unit had beed previously levered open and
messed with then gaffer taped up.
He charged me the £30 callout fee, not bad really.

He said the unit wasn't doing what it should be, so I opened it up again
and found a broken capaciter on the board.
I replaced the capacitor for 11pence from Maplin 100uf - 50v
£4.99 for a roll of self amalgamating tape to seal the unit back up.
Car fans now work fine again.

Car electrician blokey tells me there are three different types of
cooling systems on 406's - Early one's have a thermostatic switch that
turns the fans on, later Mk1's have the Bitron device like mine, where
the thermostat is just a temperature sender, not a switch.
Later HDI's the cooling system control is part of the ECU, is this correct?

Thanks for all your help

Andy D