Trunk blower? (Page 2/2)
theogre SEP 28, 12:25 PM

quote
Originally posted by Patrick:
...or turn on Defrost. Seriously. The fans will kick on..

Don't count on that.
While Set to 2 or 3 AC positions works, many to all Fiero control head and more aren't wire to turn on rad fan and engine blower in Defrost mode. Most FSM including Fiero "books" show the same info. Colorize switch to show on/off.


Note: Some Compressors may turn that on by switches on them regardless of control head wiring. I know 87+ V5 compressor does not have switch that closes for High Pressure. V5 and Many other AC systems simple Turn Off the compressor seeing High Pressure.
(Most "New" vehicles are Required by EPA etc to Shut Off for High Pressure. Older cars w/o this function often need to have them added before most shops to work on the AC and be legal. Another reason many won't touch old car's AC.)

[This message has been edited by theogre (edited 09-28-2021).]

Patrick SEP 28, 02:38 PM

quote
Originally posted by theogre:

Don't count on that.



Old threads regarding this are Here.

Ogre, please clarify.

The fans kick on when the A/C is turned on, correct?

The A/C is turned on when the HVAC control is set to Defrost, correct?

So, are you saying that even though the A/C is running while in Defrost mode, that the fans are not kicked on?
theogre SEP 28, 06:33 PM
Originally posted by Patrick: Ogre answers in Bold

Old threads regarding this are Here.

Ogre, please clarify.

The fans kick on when the A/C is turned on, correct? Yes

The A/C is turned on when the HVAC control is set to Defrost, correct? Yes and often when Weather is "warm" to dehumidify air blowing. (Compressor is "killed" at low temps because Low Cut Off is active.)

So, are you saying that even though the A/C is running while in Defrost mode, that the fans are not kicked on? Yes when Control Head does all "thinking."

Other switches on the compressor or elsewhere in the system may turn on the fan(s).
You have to "read" above diagram and likely others in Fiero FSM for a given year and sub model or engine.
Fiero V6 has many things different vs all l4 besides the actual engine.

Even if 84-86 l4 has exact same compressor... Compressors may have 1 or 2 switch holes but the switch installed in them may have more then 1 contact set etc.
fierofool SEP 28, 07:13 PM

quote
Originally posted by Jerb:

If your a/c still works and you just need cooling, disconnecting the compressor clutch connector should keep it from kicking on, but the fans will run.



Or just move the temp slider up if you don't need AC cooling. You can actually get full heat even when the AC control is set to Norm.

pmbrunelle SEP 28, 07:27 PM
I jumped terminals A and B of the blower relay socket when I wanted the blower to be hot-in-run.

A short wire loop with two thin spade terminals plugs into the socket; the mod is fully reversible.

You can also unscrew the relay from the car if you want to reduce weight/complexity.