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Ruflyf
09/20/2015, 10:30 AM
A week or so ago my blower motor just stopped working. After doing some research I found it is likely the resistor pack, blower motor, or relay. I'm trying to narrow down the possibilities as I don't want to just start replacing parts until something fixes it.

What I've done so far,

1) removed blower motor and put my meter on the wires, no power on any leads with ign in ON position and fan switch on.

2) lowered glove box and removed resistor pack plug. no power to any of the leads on the plug either.

3) switched relay E25 with E27 under the hood. This did not give me power to any lead either.

Any ideas on what to try next I would think something would have power to it when the fan switch on the dash is turned on, right?


Thanks

Keith

PK
09/20/2015, 11:58 PM
When the resistor pack throws it in, the fan normally still operate on high speed only (ie resister pack not drawing down any power so fan goes flat out.)

However in your situation the problem could just be the switch. There has to be some power floating around if the switch is on.


PK

Ruflyf
09/21/2015, 08:04 AM
Thanks PK, yes it could be the switch.

Would anyone mind dropping the glove box and putting a meter on the different leads of the plug going into the resistor pack while the fan switch on the dash is engaged? Probably needs to be a 99 so that its not climate control models.

Jayd-S
09/30/2015, 03:29 PM
Would anyone mind dropping the glove box and putting a meter on the different leads of the plug going into the resistor pack while the fan switch on the dash is engaged? Probably needs to be a 99 so that its not climate control models.

Hi Ruflyf,

I posted a step by step trouble shooter here: http://www.vehicross.info/showthread.php/26838-Heater-AC-blower-motor-problem-solving-tips!-%28For-motor-with-auto-climate-control%29?highlight=Jayd-S+Blower+motor

Whether it is auto climate control or not, the circuit diagram I included essentially is the same and it shows where to test for voltage from the battery back through the relays, switch, resistor and motor. Once you have removed the glove box, all you need to get at is easily accessable.

PK is right, the resistor block only slows the motor down, so even if all three resistors are blown, the motor will still operate with the switch in the high speed position.

Oh, and don't forget the obvious, the ignition need to be switched AND the engine running before you will get any power to the motor. There is a bypass relay that disables the blower motor circuit ensuring maximum ampage to the starter motor. Lesser power drains like the radio and other accessories are only disabled at the moment the starter motor is engaged. Don't mean to be synical, but this is easily overlooked!

Good luck!