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Old 01-27-2010, 04:46 PM   #5 (permalink)
Green Machine
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Join Date: Aug 2007
Location: Ohio
Posts: 4,689

Well one way to test to make sure it is actually the relay is to do the following (for years 95+):
  1. Grab a DMM to measure voltage.
  2. Measure voltage at the purple wire (at blower motor). On high the voltage should be system voltage and the other three speeds the voltage should vary.
  3. If all voltages are fine, blower motor is most likely bad.
  4. If no voltage is on the lower three speeds or the high speed you will need to remove the high blower motor relay (located behind glovebox).
  5. For testing voltage for the lower speeds, Check the dark blue wire pin. If voltage is present go to step 11. If no voltage is present go to step 8
  6. For testing voltage for the high speed, Check the red wire. If no voltage is present, go to step 7.
  7. Check the one connector around the blower motor (has black and red wires) and make sure it is not melted. Then check the 50A under hood fuse. If everything checks out, Go to step 12.
  8. Check your 25A Heater/AC fuse. If fuse is ok, proceed to next step.
  9. Check voltages at the blower resistor (to make sure the switch itself isn't bad).
    1. Yellow wire is Lo Speed
    2. Tan wire is Med-Lo Speed
    3. Light Blue wire is Med-Hi Speed
  10. If you have voltage on all three wires with the switch in the correct spot for each wire (and key on) then most likely the blower resistor is bad.
  11. Replace High Blower Relay.
  12. With key on, turn fan speed switch to HI. Check the orange wire at high blower relay. Should have system voltage, if you do and the high speed did not work, the relay is bad.
I think that should help.... Hopefully it isn't to confusing and hopefully i got everything written down correctly lol.
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Last edited by Green Machine; 01-27-2010 at 04:51 PM.
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