2004 buick regal

08-15-2015, 08:25 PM
I have a 2004 buick regal ls I have no blower motor, cruise control, AC, or rear defroster. All the fuses are good and I've replaced the blower motor resister and still nothing. This problem was off and on through the winter but now nothing.

Tech II
08-15-2015, 09:03 PM
Well, usually, when a group of accessories don't work, and all the fuses are OK, sometimes they all share a common ground.....

The easiest circuit to check out, is the blower motor.......remove the harness from the motor, and with a test light, check power AND ground circuits in the harness......If you have power but no ground, and attach a redundant ground to the ground circuit of the harness...

08-15-2015, 11:04 PM
I've checked the grounds and they all are good

Tech II
08-18-2015, 10:10 PM
You do realize that there are grounds all over the car? Under the carpet, under the the dash near the steering column, etc?

Did you check for power AND ground at the blower motor harness connector, with the key on, Hvac on, and the blower setting on various settings?

08-20-2015, 09:28 PM
the power and ground are good at the resister plug and at the blower motor. Used a volt meter power wire at the resister shows over 14 volts the other wires to the different switch settings don't change 3.08 volts on all. At the blower motor plug the readings are over 14 volts with the switch on high and 3.08 on every other setting.

Tech II
08-20-2015, 10:01 PM
I never test for power on high current elements(motors, solenoids, etc.) with a multi meter......is shows only potential voltage, not working voltage....for example, you attach two test leads to the blower motor harness, and the meter reads 14 volts....you disconnect the meter and attach a test light to the harness...with a 14 volt reading you would expect a bright test light....but it is dim......Why? because there is a voltage drop in either the power circuit, or the ground circuit...this can be caused by high resistance from a bad connection(arcing) or rust....there is very little current(micro amps) going through the circuit, with a multi meter(very high resistance, usually 10 megohms)....with a test light, you have 2 or more amps running through the circuit, causing a voltage drop across the bad connection.....

You say you have no blower motor working, yet you show 14 volts....So if the power side is ok, and the ground side is ok, that blower should be running, unless you have a bad blower motor....

08-21-2015, 08:12 AM
I always test motors with them plugged in-- 12.6 volts unplugged- but 0 volts when plugged in, means bad connection, burnt, corrosion etc.

08-21-2015, 04:34 PM
I now have a blower motor on hi, none of the other positions work and I still don't have cruise control or AC

Tech II
08-21-2015, 10:56 PM
My schematics don't show a resistor block, but a blower control module.....




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