HELP! H3 With No Blower For Heat OR AC. Not The Usual Causes

[diggersh3]

I am looking for any ideas on the issue I am having with my H3.

I have a 2006 H3 and the blower motor quit. It is not any of the usual suspects. I have checked all the fuses. The relays. The wiring and so on. I have replace the main heater control switch, the resistor (no burning), the high speed blower relay, tested the blower motor on a bench, and checked the continuity through the blower resistor harness with my DVOM.

I have power at the main harness for the resistor - blower - relay wiring harness connector hooks up. I have power at one terminal on the resistor plug in and power going to the motor plug. When I plug in the motor i get power through both connections back to the high speed blower relay. If I plug in the relay I loose all power.
Any ideas of what I am missing or the possible issue?

 

[H32NV]

the ground for the blower motor runs through the relay. They should have made this a PWM type system, but in their wisdom, decided that high current was better. You probably have a ground issue, so there is no return for the electrons from the motor.

 

[Hummjay]

Sounds like the GM recall. Many of us on here had similar problems with the hvac system. I had to fix this issue in July 2015. Got the recall notice #15042 in August 2015. I think these 2 threads might be helpful:

http://www.hummer4x4offroad.com/forum/showthread.php?11029-H3-blower-motor-resistor-recall&highlight=blower+resistor



http://www.hummer4x4offroad.com/for...x-fan-control/page9&highlight=blower+resistor

 

[diggersh3]

Sounds like the GM recall. Many of us on here had similar problems with the hvac system. I had to fix this issue in July 2015. Got the recall notice #15042 in August 2015. I think these 2 threads might be helpful:

http://www.hummer4x4offroad.com/forum/showthread.php?11029-H3-blower-motor-resistor-recall&highlight=blower+resistor



http://www.hummer4x4offroad.com/for...x-fan-control/page9&highlight=blower+resistor

I thought so to but the harness is fine. Confined continuity with a DVOM and even though my resistor was not burnt I replaced it with a new one.

 

[diggersh3]

the ground for the blower motor runs through the relay. They should have made this a PWM type system, but in their wisdom, decided that high current was better. You probably have a ground issue, so there is no return for the electrons from the motor.

Any Idea Where you would start for the ground? I have confirmed the grounds in the harness for the high speed relay and the resistor are indeed working as they should. This is a really odd deal. I have hit all of the normal culprits and have come up blank.

 

[H32NV]

Any Idea Where you would start for the ground? I have confirmed the grounds in the harness for the high speed relay and the resistor are indeed working as they should. This is a really odd deal. I have hit all of the normal culprits and have come up blank.

Have you applied 12V to the relay to actuate it and then check connectivity at that point? Or replaced the relay or cleaned the terminals on the fusebox underneath?