Fan Resistor Replacement

[05trail]

My Dad had his 2003 LS 4x4 Trailblazer in for a checkup the other day. I guess from what he tells me is that his high speed fan or when you select 5 on the fan speed it doesn't work. The GM peeps said it was because of a bad resister. They told him 100 bucks and it could be fixed. So.....first off has anyone come across this problem and if so how did you fix. Or what would be the steps in getting to this resister to replace it and could he just get a resister from the dealer. Any help would be great. Thanks

[tblazed]

I think the resistor ass'y (1) is about $20-25. It is located up under the dash behind the glove box. Could also be a problem elsewhere like in the HVAC control head because in high speed "5" the resistor ass'y is bypassed and connects DC power directly to the motor. Could also be the #35 40A Blower fuse in the Underhood fuse block that supplies power only in high speed "5". Good Luck with it!

http://users3.ev1.net/~epadget/resistor.jpg

[2002BlkLTZ]

I had this problem on a 2000 Chev Cavalier at one time. I think it did lose High fan speed. The resistor wasn't hard to find or hard to replace, in theory. But it took some serious contortion to get to it (passenger dash in the blower motor housing). I think the resistor was around $20-$25.

[rcam81]

I had to replace it twice in my 98 Malibu and it needs to be replaced in my daughters 96 Cavalier. Seems like none of the GM products are immune to it.

[tblazed]

As i mentioned before, in high speed "5" position, on the Trailblazer with manual a/c controls, the resistor ass'y is bypassed with a relay in the HVAC control head unit, and connects DC power directly to the motor, so the resistor is least likely to cause just the high speed to fail. A bad resistor would more likely cause some or all of the lower speed positions 1-4 to not function because that is when the resistor in in the circuit. I have verifed this by looking at the schematic diagram for the Trailblazer in my GM service info. I would certainly check that #35 fuse at the underhood fuse block first and go from there.

[dtu]

I had the same issue with my 02 envoy. speed 5 did not work. was the resistor. they replaced it under warranty (extended)

[zenorini]

My fan speed #5 doesn't work so I am assuming from this site that it is a bad resistor pack. Before I buy a new one I have seen here that you need to check fuse # 35 first. I have located the fuse under the hood. How do I
know if the fuse is bad. At first glance it looks OK. Thanks

[eeehabt]

Check out this thread

http://forums.trailvoy.com/showthread.php?t=28465

posting # 4

If your A/C is electronic, It's surely 100% the blower module.

[RayVoy]

Many, many, many threads on the topic.

The SEARCH button is your friend :thumbsup: