heater only works on high


93blueblazer
10-10-2009, 06:48 PM
i have a 99 cavalier 2.2L at trans. the blower fan for the heater only works on the highest speed. if you turn it down at all to a lower speed it just stops blowing. im not sure if it would be the switch or maybe something else. i know there is some part behind the blower fan that has to do with the fan but im not sure if it would do that. any help would be great.

Airjer_
10-10-2009, 07:13 PM
Sounds like a blower motor resistor. Check for continuity between the pins on the resistor that the orange wire and the black/white wire go to. If its open than the resistor is bad. High speed bypasses the resistor and is grounded through the switch.

PlanetDude
10-11-2009, 11:06 AM
Agree with Airjer - blower resistor. I had the same problem in the sis-in-law`s 96 Cavy, and the blower resistor was the problem.

It`s in a god-awful place (at least it was on the Z24), way back behind the blower motor on the passenger side. I seem to recall taking hte blower motor out to do it, may or may not be required.

It`s a weird size socket required too. 3/16? 5/16? I can`t remember, it was over a year ago.

Good luck - if you have any questions, post back - I`ll try and help.

Airjer_
10-11-2009, 11:28 AM
It`s a weird size socket required too. 3/16? 5/16? I can`t remember, it was over a year ago.



Its a 5.5mm (yup a 5 and 1/2 mm socket). Sears carries them now if your looking for one.

PlanetDude
10-11-2009, 12:07 PM
Thanks.... I know it was a weird one, out of my "specialty" socket drawer... I had 5 or 6 strewn across the workbench before I found one that would work. :)

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