I bought a 88 Fiero 4 cyl with air conditioning. Can't figure out how to use the darn heater and ac controls and can't find any info on the net yet. Had heater working but not sure which buttons were pushed to make it happen. Now I need the ac and I can't get the fan to turn on or any of the buttons to do anything. The fuses are all good. Is there a specific sequence to push buttons or what. My wife got the heater working but not sure how she did it and she can't get it working again. Seems silly asking this question but we are stymied.
ok guys, i'll take this one. Each button is labled. From left to right, "Max,Norm, Bi-Level (BL), vent, heater (HTR), and defrost". Max, norm, and bi-level are supposed to turn on the A/C and the engine's cooling fan at the radiator. Vent is just air out of the vents w/o AC, heater directs air to the floor ducts (with a little directed to the windshield), defrost turns on the AC (but no engine fan) and directs air to the windshield. All settings (except "max" I think) you can adjust the air temperature by taking the slider that's below the buttons and sliding it to the right for heat, left for cool. The twist knob on the far left (marked LO-HI) controls the blower motor fan speed.
This system uses a couple of electric motors to open and close doors inside of the AC/heater box based on which button you press.
Many Fiero AC systems are no longer charged with refridgerant (leaks out over time), and selecting an "AC" mode will result in un-cooled, ambient air temp only. But regardless, the blower motor should spin, and the button you press on the controler should direct air to wherever you want it to go.
the blower motor is on but not working? Stop playing and stop the car. You need to find the problem because Blower not working or heater box full of crap are a easy way to cause a Fire. Millions of car have same issue, is not Fiero. After you check/clean resistor for crap, the resistor need a lot of air flow to cool or resistor can fry or still cause fire.
Only at high speed does the blower get full power and bypass the resistor assembly. You can safety test at high speed w/o resistor problems. Nothing there? blower or controls can be dead.
Thanks for the replies. It appears that the blower motor is fine but the problem is the speed control switch in the dash. No current going through the switch. Now I'm looking for a replacement switch and can't find anything on the web or in the Fiero store catalog. I need the actual switch that the control knob slides onto. Anyone know where to get one of these?
Not sure where you can buy a fan switch other than at a wrecking yard. But you're sure that you have power getting to the switch? Have you checked the blower resistor. Do you have high speed only? Unusual to lose all 4 speeds.
Originally posted by spot65: Thanks for the replies. It appears that the blower motor is fine but the problem is the speed control switch in the dash. No current going through the switch. Now I'm looking for a replacement switch and can't find anything on the web or in the Fiero store catalog. I need the actual switch that the control knob slides onto. Anyone know where to get one of these?
does blower switch get power to it? Yes, then likely switch bad. No, then AC relay or control buttons have issues.
AC uses 2 relays Blower High speed AC Power
I think you can switch the 2 to test. is in front spare tire space. if Relay then low speeds work but high won't, etc.
Thanks to everyone who sent replies. Being new to Fieros, I'm slowly but surely learning a lot about them. Mine is a 88 with 59,000 miles on it and I bought it from the 2nd owner. Blower problem ended up being the high speed blower relay. Replaced it for $13 and things are working again. Also pulled out my resistor and found it to be perfect;ly clean- looked brand new. No leaves or rodent nests anywhere to be found. AC is still putting out cool air so I'm hoping the Freon stays in there. Not sure where to get r12 around here and I don't want to convert to r134. Thanks again for all the help!