Heater Blower Won't Work on "5"

[huminski]

Well, I have the reverse of what seems to be the common problem with the reisitor pack.... my blower motor works fine on 1,2,3 and 4, but does not work on 5. Could this still be the resistor pack or is it something else.

It would work on 5 intermittently for a while, now it appears to be completely dead.

Help me out!

Thanks.

[j cAT]

Originally Posted by huminski

Well, I have the reverse of what seems to be the common problem with the reisitor pack.... my blower motor works fine on 1,2,3 and 4, but does not work on 5. Could this still be the resistor pack or is it something else.

It would work on 5 intermittently for a while, now it appears to be completely dead.

Help me out!

Thanks.

fan switch n/g use meter to verify

[Sonny01]

You could take the resistor pack out and measure the voltage and take a look at it...mine had been on fire and it was easy to tell it was bad.

[j cAT]

Originally Posted by Sonny01

You could take the resistor pack out and measure the voltage and take a look at it...mine had been on fire and it was easy to tell it was bad.

no resistors are used in max fan speed

[Sonny01]

I didn't know that! But then I didn't know 5 was the top...I'll have to count mine but it seams like there are 6 or 7 bars. But the problem I had was on a 2000 and I think it did only have 5 settings. My middle settings were out.

[Sonny01]

I counted the bars for the fan and I have 8...not that it means anything...

[huminski]

The knob in a 2004 is labeled 0-1-2-3-4-5.

I read somewhere that resistors are used for 1-2-3 and 4, and a relay was used for 5. Is this true? If so, anyone know the location of the relay?

[rockwood84]

got to be in the relay box under the hood. the diagram is on the underside of the lid

[brcidd]

You must have a manual HVAC system, since you have described the blower motor as 5 speed operation-- automatic HVAC systems have bars indicating blower speeds and a separate processor to control speed. So....

You'll find the high blower relay is part of the blower resistor board (next to blower motor- under dash) - so you'll need to replace that if indeed the underhood fuse (40 amp) checks good. There is no blower relay underhood. Here is a description of your high speed blower operation:

High Blower Speed
When the High blower speed is selected, the HVAC control module applies voltage to the blower motor resistor assembly through the high blower motor control circuit. The voltage energizes the blower relay, causing the blower motor to be connected directly to the battery positive voltage circuit. The blower motor and blower motor relay are grounded through the ground circuit.

[j cAT]

[quote=brcidd

You'll find the high blower relay is part of the blower resistor board (next to .[/quote]

this is not true on 2000 5.3 sil. there is no relay in or part of the resistor board.

[brcidd]

Maybe I missed it- but I thought he had a 2004 Silverado-- you are correct- a 2000 has the high blower relay behind the glove box on the HVAC module-- I thought by his signature it was a 2004 .. sorry

[j cAT]

Originally Posted by brcidd

Maybe I missed it- but I thought he had a 2004 Silverado-- you are correct- a 2000 has the high blower relay behind the glove box on the HVAC module-- I thought by his signature it was a 2004 .. sorry

this relay should be mounted on the blower motor outside of the air duct where the wires connect to motor. the motor resistors are inside of the duct and the flow of air keeps the resistors from failure.....at least until the warrantee ends......

[thewaxer]

I had the same problem on my o6. after five went out it melted the wires in plug and attachment to buy new wiring kit to fix it.

[j cAT]

Originally Posted by thewaxer

I had the same problem on my o6. after five went out it melted the wires in plug and attachment to buy new wiring kit to fix it.

are you saying the wires at the relay connector overheated ? and on an 06 was this at the blower motor where it is mounted ?