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Blower Motor Resistor

I am trying to replace the blower motor resistor in my 2005 Chevy Silverado. The new part fits but the electrical connection harness do not match. Dummy me cut of the original harness. The original has three prongs and the new resistor has six. Do I need to get a new six prong harness?

It sounds to me you have the wrong replacement part for your model or year. Are you sure it is the correct one?

I would avoid cutting up a nice factory harness at all costs. It sounds like you have the wrong resistor. Try entering your vehicle information on www.napaonline.com and then search “blower motor resistor”. You should get results that will show pictures. You can match it up from there. If what you have doesn’t look like what’s on the screen, try going back or forward a model year. That 2005 Chevy might have been made in 2004.

Agreed. Sounds like the wrong part.

I’d also point out that the resistor may not be all of your problem. A resistor usually fails for one of two reasons.
One is that something (trash, etc.) enters the air ducting and gets caught on the heating coil. This leads to a hot spot and the coil burning through.

The other is a chronically dragging blower motor. A dragging motor pulls far more current (more heat) than a good motor and eventually this additional draw will burn the resistor up.

Bring the old part to get a new part and you will get the right one.

ok4450, what you said makes sense and I agree however I have replaced 2 blower motors on my van but have never replaced the resistor. The van is a 1996 Dodge.

There is a S.I from Chevrolet about replacing the harness end,

It varies and not every case is the same. Sometimes sheer luck is involved.
The same thing also applies to other electrical items. A clogged fuel filter makes a fuel pump work harder which means it draws more current which means more heat which in turn can take out relay contacts, wire connectors, and whatnot.

This was the case with the 70a/80s era VWs. The cars would quit running and many times it was traced back to the fuse block, fuse block wire plugs, etc; all burnt because of a dragging pump.

In the case of the Taurus/Sable cars a dragging blower may take out an ignition switch along with the fan speed switch as another example.

This even applies to electrical outlets in the home. Take a standard 15 amp wall socket, apply 12 or so amps to it for a while to simulate a dragging blower for instance, and eventually the wall socket will burn and/or the breaker will pop.