86 cutlass with no heat blower does not turn on at all
First, determine if the switch powers up the blower motor.Locate the blower motor.Unplug the wire connector.Determine which lead is hot and which is ground.Usually black indicates ground. Turn your blower switch on and ignition to on just before turning engine over.The blower will not be powered up on accessory(turning key back ward) . Using a volt meter check for voltage by touching red lead of meter to hot wire on connector of blower and black lead of meter to ground wire.Or use a test light.If 12 volts is not measured, switch meter to ohms or resistance.Connect one lead to chassis ground and the other to blower ground in connector.If it zeroes out you have a good ground.Run a wire from your positive post on battery to the blower and a ground wire to chassis. Hook these wires to your blower. If blower works, you should replace the switch for the blower.I would hook up the ground and run a toggle switch to the blower.It will always have full power when on, but it will work. Sometimes with these old cars when you test for voltage at the switch itself , there will be none and you can run a new power wire to the existing switch.
There may also be a relay that works in the circuit for the blower motor.If power isn't registered at the blower motor through this process, replace the relay for a few bucks first.It is cheap and might solve the problem.If it doesn't, you're only out a few bucks.
If it's not turning on at all, aside from anything out of the ordinary, that is telling me that you either have a blown fuse or the blower motor has failed. You can test the blower motor by supplying 12vdc right to the fan. The fan is located under the hood in the firewall up against the passenger side. It should have an exposed connector to the motor.
Did it quit all at once or did you slowly loose blower speeds one at a time starting with the lowest speed? If that is what happened there is a resistor in the heater duct, usually down by the firewall inside the passenger compartment of the car that has failed. They are a bit tricky to get at, but you can probably change it yourself with some basic tools. You tube can probably help you out with a how to video.
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