1.8TTony
Well-Known Member
- Joined
- January 8, 2015
- Messages
- 124
- Reaction score
- 93
- Location
- California
- City, State
- Chico
- Year, Model & Trim Level
- 2003 ST XLS
2004 ST XLT
Ok, so here's what's going on.......I turn on the air conditioner and air does not blow through the vents. Everything else seems to operate correctly. The a/c compressor clutch works, the dryer canister in the engine compartment gets cold. I can hear the vent doors moving when I select different vents, but the blower motor still does not activate.
How do I get the blower motor to work properly? This is what I've tried.......
Removed, inspected and tested #6 fuse in the fuse box located on the side of the dash......it's good. This circuit is getting power.
Removed, inspected and tested the maxi fuse in the fuse box located in the engine compartment.....
It's good. This circuit is getting power.
Removed, inspected and tested the blower motor relay in the power distribution box in the engine compartment.......it's good. This circuit is getting power.
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The following, NOT getting power.
Removed, inspected and tested the blower motor.......it's good. This circuit is NOT getting power.
Removed and inspected the blower motor resistor.......it LOOKS good, I have no way of testing this item, but it does not look damaged nor burnt in any way. The fan speed control knob has four speed settings and since none of the speeds work, I assume the resistor is NOT the problem because the chances that all four resistor circuits going bad at the same time is not plausible. Either way.......this circuit is NOT getting power.
I removed the HVAC panel knob assembly and looked at the fan speed control switch. It looks good. I have no way of testing this knob........this circuit is NOT getting power.
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Tried another thing:
Removed, inspected and tested the a/c control switch. It's good......this circuit is getting power and is sending power when activated.
So, to recap:
No power at the blower motor.
No power at the blower resistor.
No power at the speed switch knob.
Yes power at the fuses.
Yes power at the relay.
Yes power at the a/c panel switch.
In regards to the a/c panel switch, the power SENT from it is a purple wire. I assume this wire is the trigger wire to activate the a/c system and for whatever reason, the a/c system is failing to send power to the blower motor resistor or failing to send power to the blower motor speed control knob.
So what's next?!
How do I get the blower motor to work properly? This is what I've tried.......
Removed, inspected and tested #6 fuse in the fuse box located on the side of the dash......it's good. This circuit is getting power.
Removed, inspected and tested the maxi fuse in the fuse box located in the engine compartment.....
It's good. This circuit is getting power.
Removed, inspected and tested the blower motor relay in the power distribution box in the engine compartment.......it's good. This circuit is getting power.
----------------------------------------------------------------
The following, NOT getting power.
Removed, inspected and tested the blower motor.......it's good. This circuit is NOT getting power.
Removed and inspected the blower motor resistor.......it LOOKS good, I have no way of testing this item, but it does not look damaged nor burnt in any way. The fan speed control knob has four speed settings and since none of the speeds work, I assume the resistor is NOT the problem because the chances that all four resistor circuits going bad at the same time is not plausible. Either way.......this circuit is NOT getting power.
I removed the HVAC panel knob assembly and looked at the fan speed control switch. It looks good. I have no way of testing this knob........this circuit is NOT getting power.
----------------------------------------------------
Tried another thing:
Removed, inspected and tested the a/c control switch. It's good......this circuit is getting power and is sending power when activated.
So, to recap:
No power at the blower motor.
No power at the blower resistor.
No power at the speed switch knob.
Yes power at the fuses.
Yes power at the relay.
Yes power at the a/c panel switch.
In regards to the a/c panel switch, the power SENT from it is a purple wire. I assume this wire is the trigger wire to activate the a/c system and for whatever reason, the a/c system is failing to send power to the blower motor resistor or failing to send power to the blower motor speed control knob.
So what's next?!