Heater Blower Control Unit (1983 and later models) — description and testing (Peugeot 305)

1. On the latest models, the rheostat does not transmit current to the blower motor. It simply sends a signal to a control unit consisting of a power transistor and a heat sink. The control unit is located on the inner surface of the left front fender.

2. If the blower does not work, the control unit should be checked. Please first refer to B/Figure 12.115 where the unit terminals are identified.



3. Turn on the ignition and disconnect the M27C wire from the control unit. Ground the M27C terminal on the unit. If the blower starts working, either the thermostat or the control unit is faulty. If not, the problem lies in the wiring or the blower motor. Don't forget to check the fuse.

4. When finished, reconnect the wire to the control unit.

Article republished from the website [PeugeotBook]