Climate control fan problem, intermittent air flow

[ripfan]

2001 V40 1.9T, automatic

Sometime, too often, the climate control fan runs fine, then has a burst at max before completely stopping airflow into the cabin. Some of the lights on the dash also don't light-up, although I'm not sure if that's a related issue. Either way, this doesn't seem like a unique problem. From what I have read, the cheapest first possible cause to tackle is the climate control transistor.

http://canada.newark.com/multicomp/2n30 ... dp/35C0700

Is my diagnosis feasible, and is that what I should order? Thanks for helping out.

[wahiddd]

You can try replace your blower variable resistor/trim pot in your climate control module
Inside the faulty trim pot, resistor skid is worn out due to slider movement

I already did mine2 years ago. cant remember exact part no.
Piher brand PT-15 POTS with "N" rotors, 5K resistance, Horizontal Mount - Vertical Adjust

The parts is cheap. But here, quite difficult to find PT15 trim pot with "N" rotors.
Ended up dismantle new and faulty trim pot, than using old rotor with new PT15 carbon resistive.

[alschnertz]

I changed the transistor in my '01 S40 hoping to cure the surging blower fan. I had a post about it but can't find it.
It didn't make any difference. It's pretty annoying.

I'd be willing to try the rheostat that wahiddd recommends next.