Blower motor relay failure?
- Thread starter thunderstruck
- Start date
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thunderstruck
Babuinos Móviles
Okay guys, I think I *finally* got it, or at the very least solved another piece of the puzzle. I started tracing back the ground wire from the blower motor with my ohmmeter. Not far away I found a connector with a pair of 12-gauge red and black wires, one end running from the firewall, the other towards the blower relay. Ohmmeter showed high resistance between the black wires and I couldn't pull apart the connectors. While I was trying to take apart the connector, the resistance dropped. Blower motor worked again, but in about 10 seconds, the connector was hot to the touch. I cut the connector and spliced the wires. No more resistance 
Once I did that I finally pulled apart the connector. Ground wire was burnt to a freakin crisp. I can post pics of the connector later on if you guys want.
And yeah, the actuators didn't function whenever the blower motor stopped. I didn't notice this until I pressed the recirculation button and the actuator made a loud grinding noise. The controller and all three actuators are no more than five months old. Apparently they are grounded through this same wire.
Whew! One bit of advice, I think GM "overfused" these trucks. 25amps for the interior AC fuse and 50amps for the underhood blower fuse????? I think if one were to replace the interior fuse with a 15 or 20 amp and the underhood fuse with a 25 or 30, you would blow the fuse before crap like this begins to happen.
Sent from my Nintendo 64
Once I did that I finally pulled apart the connector. Ground wire was burnt to a freakin crisp. I can post pics of the connector later on if you guys want.
And yeah, the actuators didn't function whenever the blower motor stopped. I didn't notice this until I pressed the recirculation button and the actuator made a loud grinding noise. The controller and all three actuators are no more than five months old. Apparently they are grounded through this same wire.
Whew! One bit of advice, I think GM "overfused" these trucks. 25amps for the interior AC fuse and 50amps for the underhood blower fuse????? I think if one were to replace the interior fuse with a 15 or 20 amp and the underhood fuse with a 25 or 30, you would blow the fuse before crap like this begins to happen.
Sent from my Nintendo 64
Enginebuilder
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I'm really interested in where, exactly, you found the connector that failed, and where this system actually grounds at. I've been having the *exact* same problem with my '95, and diagnosed it as an intermittent ground; I've spliced an auxiliary ground into the ground circuit as an expedient fix, but would like to solve the root cause.
thunderstruck
Babuinos Móviles
If you remove the glovebox, the connector will be directly visible between the blower motor and heater core housing. Sorry I don't have any pics, and I've already binned the connector.
I have no idea where the ground is actually at, once it passes thru the firewall, it joins the engine wiring loom, which is where I lost track of it. It may be underneath the underhood fuse box.
Sent from my Nintendo 64
I have no idea where the ground is actually at, once it passes thru the firewall, it joins the engine wiring loom, which is where I lost track of it. It may be underneath the underhood fuse box.
Sent from my Nintendo 64
