Blower Motor Problem?

2005 GMC ENVOY
75,000 MILES • 6 CYL • 4WD • AUTOMATIC
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MRODRI1951
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My heater blower motor stopped working, I replaced the Climate Control Assy and the motor worked. I reinstalled all components and did something wrong because I lost all power and could not remove my key. I jumped my GMC removed my key and charged the battery. The next morning I started my GMC and the blower motor would not work. I pulled the blower motor and jumped it to my batter and it worked fine. I installed the blower motor and it will not operate via the control assy. I checked and double checked all blower motor/HVAC fuses and swapped the relay under the good with another function relay but still no blower motor operation. Suppestions please.
Feb 3, 2010 at 5:19 PM
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FACTORYJACK
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Is this an automatic, or manual climate system? It makes a significant difference in the schematic, and components involved. Lets start by checking the motor this guide will help.

https://www.2carpros.com/articles/blower-fan-motor-works-on-high-speed-only

Here are the blower fan wiring diagrams so you can see how the system works. Check out the diagrams (Below). Please let us know what happens.
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Feb 3, 2010 at 10:50 PM
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MRODRI1951
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It's a manual system, meaning the driver selects temp with sliding dual temp controls.

Thank You
Feb 4, 2010 at 12:44 AM
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FACTORYJACK
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According to my schematic, check first the blower fuse 40amp in underhood fuse block. With a test light to ground, check for power at blower resistor terminals G, B in lo, A in med 1, D in med 2, C in med 3, and F in hi. Check for ground on pin E. If you could use this ground to ground your test light when checking the above, it will validate it. If you have power and ground (the resistor can be disconnected) on these, and no power or ground to your blower, than replace the resistor. The resistor is shown attached to the blower motor.
Feb 4, 2010 at 8:48 AM
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FRANKIEBOY
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I have a 2005 GMC Envoy which the main blower motor does not turn off even when the truck is off and key is out the ignition and stays on it's highest level. Would it be the relay and if so where is it located? Please help it's cold up here in the NorthEast country.
Jul 28, 2020 at 2:07 PM (Merged)
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WRENCHTECH
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I assume you have Auto Temp Control. That is usually caused by the blower speed control module which is located where the blower motor resister normally would be, next to the blower motor.
Jul 28, 2020 at 2:07 PM (Merged)
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LBH
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I have a 2003 GMC envoy with front and rear heat and ac. The front heater fan stop working. the rear system is still working fine. WHAT CAN I DO?
Jul 28, 2020 at 2:07 PM (Merged)
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JACOBANDNICKOLAS
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Does the fan work on any speed? Have you checked fuses?
Jul 28, 2020 at 2:07 PM (Merged)
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EGUNS80
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My blower motor only works on 4 and 5. i have nothing on 1, 2 and 3, is it a blower motor or something else?
Jul 28, 2020 at 2:07 PM (Merged)
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ASEMASTER6371
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Good afternoon,

The most common issue is the blower resistor. I will attach the procedure and the picture of the location.

Roy

Procedure

REMOVAL PROCEDURE
1. Remove the right closeout/insulator panel.



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2. Disconnect the blower motor resistor electrical connector (3).
3. Remove the blower motor resistor mounting screws (2).
4. Remove the blower motor resistor (1).
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Jul 28, 2020 at 2:07 PM (Merged)
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EGUNS80
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Where is the panel located?
Jul 28, 2020 at 2:08 PM (Merged)
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ASEMASTER6371
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On t b.c. e end cap of the dash and under CD where your knees are.
Jul 28, 2020 at 2:08 PM (Merged)
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RODALLEN36
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i have a gmc envoy 2003 75,000 v6 Ihave checked the fuses and they are ok and i can hear something trigger when i raise the speed on the fan but nothing comes out then after about 30min i can feel heat but i sill can't hear the fan blowing.
Jul 28, 2020 at 2:08 PM (Merged)
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BLACKOP555
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check for 12v at the blower motor if thers juice change the motor with a new one!. if nothing there check for cracked or cut wires also the relay..
Jul 28, 2020 at 2:08 PM (Merged)
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IH619
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The heater blower just stopped working. I was wondering if it could just be a fuse or has the motor just died? Seemed very abrupt it was working fine then i got in the car this morning and the blower would not come on. It also could be the switch What is the best way to troublr shoot this. I looked and can not fine the fuses.
Jul 28, 2020 at 2:08 PM (Merged)
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RASMATAZ
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Direct battery voltage to the blower motor and see what happens if it comes on could be the resistor/blower motor relay/control switch/fuse-
Jul 28, 2020 at 2:08 PM (Merged)