I need to tap the knowledge base of the group. My blower fan would work intermittently, when it wouldn't work i would close the glove box with a little more force than needed. (sort of slam). It would then kick on, a bad connection. I had this happen in the past and took out the blower and took it apart and cleaned the armature and brushes. then it worked for another six months or so before needing to slam the glove box on occasion. I took it out and did the same cleaning process as before. Except now when i put it back in it didn't work at all. In fact the AC button located between the fan speed selector and the temperature selector won't light, must of blown a fuse. I checked the fuse in the box located behind the battery in the engine compartment. It wasn't blown, I checked all the fuses, i checked the relay, hooked it up to my multi meter and touched a nine volt battery to the terminal, it clicked and continuity between the other 2 terminal flowed. I pulled the panel that houses the 3 controls , fan, temp and air flow sectors. I puled the connector from the fan, It had 4 wires that i presume go to the fan speed resistor located in the air duct near the blower motor. It also had a much thinner gauge wire (yellow i think) that had 12 volts showing on the meter. When i completed the circuit to a fan speed terminal, the voltage dropped to almost zero. In my research i came across that this should drop and turn activate another relay to I presume to turn on the higher power needed.
So to recap, I bought a new blowers motor and speed reducer resistor and installed them. It seems to me that I'm not getting power to the whole AC System. The A/C on and off button won't light, no power. I've looked up wiring diagram for this truck but I'm not sure on how to interpret them. So I am looking for some direction on where to look, since i don't know were all the components are located in this truck.
So to recap, I bought a new blowers motor and speed reducer resistor and installed them. It seems to me that I'm not getting power to the whole AC System. The A/C on and off button won't light, no power. I've looked up wiring diagram for this truck but I'm not sure on how to interpret them. So I am looking for some direction on where to look, since i don't know were all the components are located in this truck.