With switch removed from vehicle, test with a self-powered test light or ohmmeter. Connect one test lead on terminal No. 3. See Fig 1 . With all switches in NEUTRAL position, continuity should exist between terminal No. 3 and terminals No. 4 through 11.
Push all 4 window switches forward and hold in that position. Terminals No. 5, 7, 9 and 11 should lose continuity to terminal No. 3. Push all 4 window switches rearward and hold in that position. Terminals No. 4, 6, 8 and 10 should lose continuity to terminal No. 3.
Remove test lead from terminal No. 3 and connect it to terminal No. 2. With all switches in NEUTRAL position, only terminal No. 1 should have continuity to terminal No. 2.
Push all 4 switches forward and hold in that position. Terminals No. 5, 7, 9 and 11 should have continuity to terminal No. 2. Push all 4 switches rearward and hold in that position. Terminals No. 4, 6, 8 and 10 should have continuity to terminal No. 2.
With lock-out switch in lock position. Terminal No. 2 should not have continuity with any other terminal. If any switch does not test as indicated, replace complete switch assembly.

Fig 1: Master Switch Terminal ID (Crown Victoria & Grand Marquis)

Courtesy of FORD MOTOR CO.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Master Switch