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2009 chevy
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6,513 Posts
I then had a friend turn the blower on so I could see if any power was getting to the motor - 14V at every speed 1-5. Now does this mean that it could still be the resistor pack (I don't see how seeing as the motor is getting power from the battery) or is it in fact the fan?
Ok, Patrick, the LS should have the manual HVAC (not the auto digital unit); so, your speed is controlled by a resistor unit. The resistor (the size selected by the speed knob) and the motor form a voltage divider circuit. With a completed circuit, the lower speeds should provide a lower voltage at the motor terminal.

However, for this circuit to function properly, a ground is required.

For you to read full battery voltage at the motor terminal, the circuit is open between the test point and ground.

You can do 2 things to check. Using your volt meter, see if there is any voltage on the motor ground terminal when you have voltage on the motor hot terminal. If you do, you have a bad ground. If you don't, you have a bad motor.
If it is the ground, that circuit completes through the speed control resistor unit, so it could still be a bad resistor unit.

mine is workin on every speed but 5 and i donno what to do either:mad:
dirtslinger, you have a manual HVAC as well. Check fuse # 44 under the seat. If it's good, you need the resistor unit.
 

· Registered
2009 chevy
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6,513 Posts
The reason the voltage does not change, is because there is no current flowing through the resistors.

I've not had mine apart, but you found a battery terminal on the motor, is there a ground terminal that you can access?

If you have voltage (14 v) at this terminal, the ground is open. No voltage, the motor is open.

Is there a ground terminal at the motor?
 
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