P1812 FORD – Transmission 4-Wheel Drive Mode Select Circuit Failure

P1812 FORD Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

P1812 FORD Possible Causes

Faulty Transmission 4-Wheel Drive Mode Switch,Transmission 4-Wheel Drive Mode Switch harness is open or shorted,Transmission 4-Wheel Drive Mode Switch circuit poor electrical connection

P1812 FORD Description

With the key in the ON position, the 4WD module (PCM) receives the operator’s choice of 4-wheel drive selection from the mode select switch (MSS). The 4WD module (PCM) then controls the electric clutch and shift motor. If the transfer case is not responding to the operator’s intentions, systematically check all inputs and outputs to the 4WD module (PCM).