A/C blower ques.
Drifting
Joined: Jul 2000
Posts: 1,266
Likes: 0
From: Allen, TX, USA
Seems very strange. Fan switch is not connected to AC...
Maybe loose connections aggravated when the unit is moved around when switching on the fan. I had the opposite before. High wouldn't work. Turned
out to be the relay and bad wires...
Maybe loose connections aggravated when the unit is moved around when switching on the fan. I had the opposite before. High wouldn't work. Turned
out to be the relay and bad wires...
Safety Car
Joined: Jun 2002
Posts: 4,764
Likes: 2,513
From: Buckeye, AZ
St. Jude Donor '12-'13
I had a similar problem with my high speed fan relay. Get the schematic...the circuit is not very complex. There are three resistors which are mounted on the top inside of the blower assembly. These are know to burn out as well. The relay simply switches the power through the various resistors to obtain the desired speed. Once you find which wire is for which speed and the motor wire you can simply take a piece of home wire and go across the relay for each spped to dtermine if the relay is bad. If all speed work direct to each wire, the relay is bad. You can do voltage or ohm check on the resistors.
Safety Car
Joined: Jun 2002
Posts: 4,764
Likes: 2,513
From: Buckeye, AZ
St. Jude Donor '12-'13
I had a similar problem with my high speed fan relay. Get the schematic...the circuit is not very complex. There are three resistors which are mounted on the top inside of the blower assembly. These are know to burn out as well. The relay simply switches the power through the various resistors to obtain the desired speed. Once you find which wire is for which speed and the motor wire you can simply take a piece of home wire and go across the relay for each spped to dtermine if the relay is bad. If all speed work direct to each wire, the relay is bad. You can do voltage or ohm check on the resistors.
