This has been a problem on my 03 S40 for over a year, when I ordered the resistor, I got 5 of them and have popped in a couple, today I had troubles starting the car and after I got it started, I had no power to the blower motor.

The resistors that I got were not the strong ones and the MJ802 seems to be the one to make sure you use.

I ordered an RU419 by smp, am not sure which resistor it uses but it should be much better than my old one. I wish I would have ordered an original Volvo but I already got the RU419 on order. I may cancel in the morning but if it has a good resistor, I will keep it.

As far as the car not starting, I overhauled the PNP switch about six moths ago and it has been good until about a week ago, this is the second time I have had troubles. I did the moving the shifter back and forth and that did not help, tried neutral and a few other things and FINALLY I did something I have never done before and that was to use my power locks to unlock and lock the car while cranking ignition and it fired right up so this has me perplexed if I should buy a new PNP switch. The original one was pristine when I did the overhaul, it was riveted with 9 rivets I had to drill out and the bolt back together but I was amazed how clean it did look inside.

Also on the blower motor resistor, aside from the main resistor, there is a small tiny inline one that has two white wires going to it, it would seem to me that it is probably best to just replace instead of replacing the one resistor but not the other.....?

 

Well I cancelled my order for the RU419, I could not confirm what type of resistor it had so I turned around and bought a genuine Volvo with the mj802, hope it is worth the extra $25.

 

Guess i am talking to myself....anyways got the genuine Volvo resistor today and am going to put it in now, glad I went with original but time will tell.

 

We are watching and listening. let us know if your issue is fixed or not. Always great to add your experience to the corporate knowledge.