Hi Roy,
Yes mine is an Espace 3.
I've changed the temperature sensor under the airbox, but it made no difference.
When I switch on the air con, the fan comes on a few seconds later. It doesn't sound like it's running at low speed though... I couldn't imagine it running much faster!
Would I be correct in thinking that the fan speed is controlled by the two relays mounted on the fan housing? The larger one being high speed and the smaller one low speed?
James
That sounds correct. IIRC the relays are 40 and 60 amp. The fans get their feed through these but it is the computer that controls them. You may be surprised when you hear the fans at high speed as they can be really noisy but as they are not often heard from the near front (you are normally sat inside sitting in traffic!) you don't realise it.
You can test the wiring to the relays and test the fans easily enough if you understand electrics. There will be a live feed to each relay, which will be a big red lead, so that should have battery voltage. When the relay is switched on, that voltage gets transferred to the output. The relay switching is done by the computer so that is usually what we call 'earth switching' - in other words, the earth side of the relay is switched to earth by the computer, normally it would have no earth and other side of the relay switching is already powered (ignition IIRC).
In DIN numbers 85 and 86 are the relay switching connections, 30 is the main live feed and 87 is the output to whatever it is being controlled. Sometimes 30 and 87 are switched around but it doesn't matter, the relay when switched on connects 30 to 87 otherwise they are open circuit.
It you have an ohmmeter, check the resistance across each motor to check if they are O.K. Check the supply to the relay both main and switching feeds. I suspect either you have a motor or wiring fault. It could also be one of the relays, so if you say it works at low speed that relays seems O.K. so check the larger 60 amp one. I have had to replace one of those before.
Roy