Disco 2 Discovery 2 Aircon Blower woes

I have been struggling for a while now to get the cabin air blower to work, in February iw wavered for a bit then went off completely, the lcd screen still shows the fan with 4 portion's for speed. I have the Climate control version of the Discovery 2 aircon, so far I have:

• Powered up the fan on the bench and proved it runs
• sorted out the seized main aircon can under the front grille
• Had the aircon re-gassed and checked
• replaced the Transistor/resistor unit
• replaced the aircon control unit

its getting to the point where there are few components left to check?

any ideas would be appreciated

You should have asked before changing parts randomly(i mean transistor and aircon ecu) cos the problem is elswhere, some simple checks you have to do, to reach the blower's plug and measure voltage in it conencted cos most probably it's a bad contact on that circuit and the voltage drops under the motor's load or if no voltage at all the blower relay or the power relay is gone.... i presume you checked fuse F7 interior fusebox though

I had a similar problem.
The fan should run full blast as a default if your climate control unit is working.
My problem was that although the positive feed at the interior fan was reading 12 volts, when the fan was switched on it tailed away to zero.
My solution was to get an auto electrician to wire in a temporary feed direct from the fuse box under steering wheel.
The positive feed for the fan is for it alone so an alternative feed should not affect anything else.
Alternatively look at the electrical library and circuit diagrams to trace feed.

sierrafery said:

You should have asked before changing parts randomly(i mean transistor and aircon ecu) cos the problem is elswhere, some simple checks you have to do, to reach the blower's plug and measure voltage in it conencted cos most probably it's a bad contact on that circuit and the voltage drops under the motor's load or if no voltage at all the blower relay or the power relay is gone.... i presume you checked fuse F7 interior fusebox though

Click to expand...

yes the fuse is ok, and all connectors seem ok, but I will get my millimeter out later

multi-meter