1999 Dodge Ram Blower motor not working

Tiny
KSDAVID
  • MEMBER
  • 1999 DODGE RAM
  • 5.9L
  • 6 CYL
  • TURBO
  • 2WD
  • AUTOMATIC
  • 360,000 MILES
Blower motor works when directly atatched to battery. When key is turned on to Acc. Blower motor relay at fuse box in engine compartment activates. All fuses are good. I am getting 12v current at both terminals on the two terminal pigtail supplied to motor, one side blk/tan the other green.

I need a schematic of the electrical circuit from ignition switch thru fuses, relay, motor, resistors, switch etc.

I'm thinking I have a short as both of these terminals should not be 12v. I.E. One should be 12v and the other ground, so as to supply the complete circuit thru the motor.
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Monday, October 6th, 2014 AT 2:38 PM

6 Replies

Tiny
CADIEMAN
  • MEMBER
IF I REMEMBER CORRECTLY FOLLOW THE BLOWER MOTOR POWER WIRE BACK TO THE BLOWER MOTOR MODULE. IT IS MOUNTED IN THE TOP OF THE A/C CASE.
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Monday, October 6th, 2014 AT 3:48 PM
Tiny
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Thanks but I need a wiring diagram with components listed. My truck is a diesel 1999 5.9l, don't know if that makes a difference. I would like to see where wires are supposed to be routed. Somebody may have been here before.
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Monday, October 6th, 2014 AT 4:00 PM
Tiny
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A diagram is not going to tell u if the blower module is bad u will need to install another one
and the blower motor will work.
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Wednesday, October 8th, 2014 AT 5:15 AM
Tiny
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Fixed it. It wasn't the module but instead it was the 40amp fuse that was blown but still making some contact. The reason I had current to both sides of the blower motor was that power was going thru the fuse enough to register on the meter on the supply side and current to the ground side is designed that way to turn off the blower motor when a/c switch is in the off position. Current on the side that comes out of the blower motor travels to ground thru the resistors to the blower motor speed control switch at the dash.

When the A/C control is switched to the off position current is supplied to the blower motor thru the resistors and keeps the fan off as current to both sides of the fan won't flow thru it. When the A/C mode is switched to the on position a path to ground from the blower motor to the fan speed switch is established.

I got a copy of the electrical diagram from the actual shop manual and this helped me see how the current is routed. Dodge does indeed have the current flowing backwords as some others have posted on this sight.

Basically it current travels like this: Ign switch on accesories to blower motor relay in engine compartment fuse box to 40amp fuse in same box to blower motor then from bm to ground thru resistors to fan speed control switch on dash panel.

Thanks for your effort at helping me out.
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Wednesday, October 8th, 2014 AT 12:08 PM
Tiny
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  • MEMBER
CONGRATS MY FRIEND
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Wednesday, October 8th, 2014 AT 5:18 PM
Tiny
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CONGRARDS MY FRIEND
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Wednesday, October 8th, 2014 AT 5:18 PM

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