Pontiac Grand Prix Blower Speeds Not Working

2005 Pontiac Grand Prix. Engine size 3.8. New blower motor. Question:
The blower motor stopped working in my '05 Pontiac Grand Prix. Using my volt meter, I checked for voltage at the blower. With the fan set to the highest setting, I saw 12 volts so I thought the blower motor was bad replaced it.

The new motor ran for 5 seconds then stopped. Still getting 12 V at highest setting and 6V at lowest fan setting. I've read that if the resistor goes bad, the fan will operate only at the highest speed, however mine doesn't operate at all. Any suggestions?

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ANSWER:

Your system works a little different. No separate circuit for high only. The blower resistor / control module controls all speeds, and the ground for the blower- circuit 2150 BLK wire. Need to put the volt meter, or better yet a test light, in the blower connector. Test light will light if you have power in and ground. Sounds like you probably won't.

Sounds like the resistor / module is bad. Also check the plug on it for burned terminals. The module also has a ground behind the radio on the cross beam.

Pontiac Blower Motor Resistor Location

Question:
1997 Pontiac Grand Prix. Replaced seized blower motor and faulty resistor. The blower motor works only on high mode, the lower modes do not work and also its affecting the daytime driving lights when blower speeds is used.

Answer:
Could you please give me a little more info. The blower motor was seized, and the resistor was replaced. Did either show any signs of corrosion or discoloration at the electrical connectors? Any other odd electrical problems before the replacement of these parts? Any other info will be helpful. Thanks and I will wait for your reply.

Visitor Reply:
no corrosion at all on terminals what its doing is this problem was their before the blower and resistor was replaced. The problem was the DRL lights go off when blower motor switch is used and go back on when the switch is off. Also the blower motor only works in high mode after a slight delay. What I'm hearing is the relays clicking in the day time driving light module when the blower switch is used. Thanks any questions let me know. Thanks.

Answer:
OK, i think i found something to be of help. After looking through several wiring diagrams, i have found that the Daytime running Lights Module and a power input to the a/c control head share the same fuse (DIC/HVAC) There is also a DRL diode in the system. The module and the diode are on the lf. side/under the dash.

We need to find out which part is clicking erratically. Apparently there is some electrical back feeding going on, and effecting the DRL/headlights. I wound suspect a faulty DRL module, but the diode may be the original problem, causing the module go bad. Hope this was helpful. Let me know what you find.


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