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T12/9 Pump Motor Polarity Bridge Description

T12/9 Central Locking Pump Motor Polarity Bridge Description

Terminal T12/9 is a bridge that reverses the operation of the central locking vacuum/pressure pump motor. It is a red wire located in the vehicle harness that connects T12/9 with either T12/7 or T12/8. This information is given as an explanation only, no repairs should be required for this circuit.

Audi 100, S4 (cars with the electric door lock switch on the driver door):

T12/7 bridged to T12/9 = vacuum unlock/pressure lock

Audi 90 (cars with switch on vacuum/pressure door actuator):

T12/8 bridged to T12/9 = vacuum lock/pressure unlock