HVAC blower motor

[JKmotorsports]

Thanks bro
Yea, I'm over at pt.net also under the same user name.
I thought about going with the STS kit also, but decided on the maggie for the flatter tq curve.

 

[TIM Z]

Thanks bro
Yea, I'm over at pt.net also under the same user name.
I thought about going with the STS kit also, but decided on the maggie for the flatter tq curve.

Good choice, i think a bigger vehicle likes the maggie better, they seem to get everything moving .

Im still a member but last time i was there there were guys running maggies running low 12's, KYsilverado ( roger) and Trevor i believe.

I need to get back and do some reasearch LOL!

 

[atjones44]

To bring this back from the dead....Im working on a buddys '99 caddy escalade.
his blower motor doesnt work at all. ac or heat. the rear ac works ok though.
To provide as much info as i can...I can turn the switch to high and feel the relay click in the glovebox. the blower motor never moves...Is this the motor that needs replacing or could it be the blower resistor.

Thanks, and this is my first post on this forum

 

[TIM Z]

To bring this back from the dead....Im working on a buddys '99 caddy escalade.
his blower motor doesnt work at all. ac or heat. the rear ac works ok though.
To provide as much info as i can...I can turn the switch to high and feel the relay click in the glovebox. the blower motor never moves...Is this the motor that needs replacing or could it be the blower resistor.

Thanks, and this is my first post on this forum

Welcome and glad ya brought it back from the dead!

I havent checked mine yet as i just got it back from the body shop ( had some paint work done.)

Any way did you check the plug on the blower motor to see if you have power there first?

If you have power i bet your motor needs replaced.

Let us know, Good luck.

 

[TIM Z]

Well, i still had no luck in getting the blower to work on high.

So i took apart the dash again, wiggled the wires around the fan speed switch, and no High works!

Dont know why, but thank god i ve better heat now!

Just thought i'd post to maybe help someone else!

 

[pmdogg]

i have the same problem with my yukon xl 2000
i just want to know if you have changed the blower

because i have 12v on the plug but the speed 5 still no works
it is the blower i need to change
thx

 

[TIM Z]

i have the same problem with my yukon xl 2000
i just want to know if you have changed the blower

because i have 12v on the plug but the speed 5 still no works
it is the blower i need to change
thx

No its the relay under the pass side of the dash, ive put 2 of them in my wifes Tahoe.

 

[pmdogg]

do you have shema or picture of the location of this relay
because me i got 12v on the plug going to the resistor but from the resistor to the blower motor 0v when i put on setting 5 i realy dont know whats the problem with the high speed setting

 

[pmdogg]

resolved just a 25amp fuse in the hood fuse box now the horn lol

 

[goose40]

Thank you, that clears it up for me as well...

The resistors have nothing to do with the high speed setting, only the slower speeds. The resistors provide resistance in the circuit, dropping voltage to the blower motor to slow the motor speed down. On high, the blower receives full voltage through the blower relay. If you had High but no other speeds, then the resistor pack is usually the culprit.
If you have all other speeds but high, the most common problem is going to be the blower motor itself, relay, or the switch panel. You can check this by turning the fan speed to "high", unplug the blower motor, and check to see that you have roughly at least 12v at the plug. If you have 12v, that means the switch panel is activating the relay and the relay is working. Over time, heat kills the magnetic properties of the magnets inside an electrical motor. Without enough magnetic energy, you may not get enough opposing force to spin the rotor full speed when the windings energize, but still enough to spin at lower speeds.
Another thing you can check is the connector at the blower motor and the switch panel. Sometimes these will heat up, start to deform, and cause a bad connection. The bad connection may be able to handle the lower current draw on low speeds, but the higher resistance from the bad connection won't be able to handle the higher current while in the full speed position.

Excellent post! Thanks for helping me with my troubleshooting. Long story short, '99 OBS 2-dr, fan blows on all speeds weakly, gets better if I "fix" it with a rap to the blower cover (not hard, I just have to tap it a little). Seems like resistor is working since fan changes speeds with switch position (incl max). I suspect the blower motor is going bad (it's the original).

BTW it's a real ******** to get at the resistor in a '99 even after popping off the glove box door because all of the passenger side airbag crap leaves about 2.5 inches of clearance between the top of the heater airbox and the underside of what's above it. It looks like I will have to remove the dash to be able to get the motor out when it finally quits.

Thanks forum folks, I'm always getting great info here!! (Like the day I learned how to turn off my DRL's...)

Steve