Heater blower will not run

WOODMASTER2358

MEMBER
1994 LINCOLN CONTINENTAL
160,000 MILES

AC compresser went bad so we put on a by-pass pully to get rid of the AC. When the blower for the heater was turned on the fan ran for about 2 seconds and has not come on since. All fuses check out OK. There is a printed circut board in the blower housing. I can here the relay on the board clicking when the dial on the dash is turned to high. I could check the input voltage but I do not know what to look for. The fan can be turned by han and runs freely.

Mike

1 Reply

DRCRANKNWRENCH

MECHANIC
3,380 POSTS

The blower motor resistor may be bad and need replacement. I could not find its location. It is probably electronically controled and is part of the circuit board. The only other component other than the motor is the speed controller. Ther eis no information on testnig it. I provided a diagram which shows its locations. The reason there is not any test information is that the system being electroically controlled, all test are circuit board level and would require a special fixture or knowledgeof the board that is not provided by the maufacturer.
The only test I can think of to make sure the blower motor is getting power is to check the connector terminals at the motor. With a multi-meter, check to see if the terminals have 12 volts available to the motor. If it does have power at the terminals the motor needs replacement. Otherwise it is one of the electronic components.

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