help !!! no blower fan on my 1969 vette
07-03-2012, 11:36 PM
#1
Burning Brakes
Thread Starter
help !!! no blower fan on my 1969 vette
Help please. I can not get my heater and a/c fan to work at all in any setting. I tested the fan and it works but not with the switch. I did order a new cut out relay to try. thanks
07-04-2012, 12:59 PM
#5
Burning Brakes
Thread Starter
Thanks Roger, I must tell you that although I am pretty good at mechanical issues, I don't where to even find the resistors on the a/c core. I will try to research more. Tks again. Jim
07-04-2012, 01:08 PM
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07-04-2012, 01:10 PM
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Here is the AC schematic on your car... 
07-04-2012, 01:29 PM
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Go to the resistor on the firewall and test for power. This connector should have light green, dark blue and light blue and yellow wires in the connector.
The dark blue wire (1 at the resistor is ouput voltage) carries power from the resistor to the blower motor.
So with the blower on any speed but high, test for voltage on the dark blue wire with the connector plugged in. If you have voltage the issue is from there to the blower motor. If you don't then pull the connector off test for voltage on any of the other three wires... (with the switch in any position but high). There should be 12 volts present on one of these three wires based on the position of the switch in the dash. If no voltage the issue is inside the car. The power hits this resistor on three different wires when not running on high. Each wire picks up a different resistance inside the resistor which gives you multiple speeds.
High blower speed is direct on the other dark blue wire... It runs from the blower switch inside the car to the 2 position on the high blower relay. Usually if there is a problem in the relay or a connection problem at the relay you'll lose high speed but maintain the others.
The dark blue wire (1 at the resistor is ouput voltage) carries power from the resistor to the blower motor.
So with the blower on any speed but high, test for voltage on the dark blue wire with the connector plugged in. If you have voltage the issue is from there to the blower motor. If you don't then pull the connector off test for voltage on any of the other three wires... (with the switch in any position but high). There should be 12 volts present on one of these three wires based on the position of the switch in the dash. If no voltage the issue is inside the car. The power hits this resistor on three different wires when not running on high. Each wire picks up a different resistance inside the resistor which gives you multiple speeds.
High blower speed is direct on the other dark blue wire... It runs from the blower switch inside the car to the 2 position on the high blower relay. Usually if there is a problem in the relay or a connection problem at the relay you'll lose high speed but maintain the others.
Last edited by Willcox Corvette; 07-04-2012 at 01:32 PM.
