Where is the blower or fuse for the blower on a 1992 Buick Roadmaster?

Answer 1

The fuse panel is accessed by opening the front door, the panel in on the end of the dash. A cover pulls off. HVAC blower is fuse 17. It is a 20amp fuse. The fuse in my #17 spot is a 25 amp fuse. In anycase, I had a few problems with the blower etc on my 1992 Roadmaster. Here is what I found. This is all under the dash on the passenger side of the car. You need to remove 4 screws holding the lower dash panel under the glove compartment. Took out fan motor to test it - this was not easy, you have to move the ignition module aside - it works ok. This was a waste of time, I could have just checked it by connecting the purple wire from the motor connector (motor connector is 2 wires, 1 purple, 1 black) to the orange wire in the controler connector. Of course I didn't have a wiring Diagram at the time. Need to find out what the 4 wire / tandem connector on the resistor block does so that I can try a temporary bypass. Took out resistor block, it seems ok, voltages check out. Turns out the resistor block is not a resistor block.. It is a large aluminum heatsink with a black transistor module fastened to it. Take the tandem wire connectors off before removing the module. The heatsink is held on to the housing by 3, 1/4 in screws. You don't need to undo these. There are 3, 5/16 in screws that hold the housing to the blower assembly beside the 3 smaller screws. 4 wires on the tandem connector, 3 on one connector, 1 orange one on the other connector. 1) Orange - power + always on, even when the car isn't 2) Purple - to the fan motor + 3) Grey - control wire + to -, variations translate to variations in the purple wire from 6 to 14 volts 4) Black - ground - Though the voltages check out, they don't generate enough current to turn the motor. A manual twist of the blower motor shows that there is a small amount of current going through. Diagnosis: blower controler brick is toast. - so�.I took it apart and was impressed with the contents. Nicely put together with that snotty gel that IBM used to use in its early mainframe computer chip casings. Noted what appeared to be 2 large surface mount Transistors and one smaller one. I mangled the circuit board during the take-apart and that gel was giving me the heaves so I didn't try to map out what the circuit was doing. Possible hack? Resistors-only are out since the fan would always be on, even when parked with engine off. If you want to manual switch this though, substitute an old halogen headlight for the control block, it generates heat too for the defrost aid. - make sure it doesn't touch any of the plastic inside though. And replace it with a real brick as soon as you can. To replace the solid state devices, there looks to be 3 of them, you will need to design the circuit to handle 20 amps at 12 volts Or 240 watts. (although I was able to get the fan motor going pretty fast with a 1 amp trickle charger) If you can mount them on the aluminum heat sink in the old brick you should have plenty of cooling though since is sits in a direct path of the fan output. The part number for this module is DELCO 16061602 with an additional number STK6994J. Appears to be made in Japan. One other note, this module sits inside the vent system at the bottom and is prone to having water sit on it from the air-con. Since the orange wire is always on, the water can cause the connector from the brick to the orange wire to crystalize and break. (It is a brass or copper connector). If this happens, and the module is still OK, you should be able to dig down and find some viable copper to resolder a new connector on.

Did you check the blower relay? You seem to know very much about electronics. Sometimes k.i.s.s. is easier.