Blower Speed 1 Inop

Beer Belly · July 31, 2010

I can understand a Blower Resistor going bad and only getting the highest fan speed....but the lowest speed going bad ???? (2006 Silverado)....could it still be the Resistor ???

digitalembrace · August 2, 2010

I can understand a Blower Resistor going bad and only getting the highest fan speed....but the lowest speed going bad ???? (2006 Silverado)....could it still be the Resistor ???

Yes it can! I had lost 1,2,4and then finally 3 and 5 in mine and it was the resistor. Oh yes, the other thing that GM never recalled but knows about that causes the blower to stop working alltogether in a lot of the 2000 era trucks is the connection at the ballast resistor. There is so little metal at the terminal on the harness and so much current that it often heats up and the terminal will burn the plug and cause a loose connection and or burn off.

So common that GM dealers carry a new plug with leads attached to wire (crimp) into your existing leads.

Beer Belly · August 3, 2010

Thanks Mike, I did a quick search and found that some were smelling something burning on Speed 5....it was the Harness you speak of. I'm gonna look into the cost of a Resistor and Harness, or I just may live with it till it gets worse.

digitalembrace · August 3, 2010

Thanks Mike, I did a quick search and found that some were smelling something burning on Speed 5....it was the Harness you speak of. I'm gonna look into the cost of a Resistor and Harness, or I just may live with it till it gets worse.

Your truck probably has either one of two models of that resistor. AC delco part #1581086 or #1581087 or you could use standard motor part # RU371 or RU571. Personally, I will not go with the GM unit as it was a printed circuit board with a coating that came off and the aluminum circuits corroded. Go with an aftermarket using wire wound resistors with an epoxy coating and save enough for a case of beer. You will have to put up with the fresh epoxy smell for a couple of days. Check out Rockauto for a listing by make and model and other differences.

I used the RU371 which was not the right model even though my local parts store said it was the correct four hole model. Electrically they are identical but the connection plug is at different angles and two more locating holes. Newer model, new #, more money. I just trimmed the top off the cover because of the different angle of the connection point, and it still held it tight in place and hell I saved a couple more dollars and it works well with no leaks from the air vent. As for the harness, look at the pins. If it is has not been badly heated up and the plastic is not melted, sometimes a little wipe or scrape and push of that terminal a little toward the center of the cavity on the large lead will connect good and may be all that is required to hold you over.