Power Window Express Down Function Inoperative

POWER WINDOW EXPRESS DOWN FUNCTION INOPERATIVE

DIAGNOSTIC FAULT INFORMATION




Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure Initial Inspection and Diagnostic Overview.

CIRCUIT/SYSTEM DESCRIPTION
When the drive power window switch is pressed momentarily in the down position past the first detent, the window will express down to the full open position when the switch is released. To cancel the express down operation, momentarily press the driver power window to the up position.

DIAGNOSTIC AIDS
- The drivers power window switch is closed to ground in the rest position on both window terminals. When the switch is engaged one of the circuits switches to power completing the circuit.
- The power window actuators are bi-directional.
- The power window actuators have a time out circuit, which will open the circuit after power is supplied for more than 30 seconds.

CIRCUIT/SYSTEM VERIFICATION
Ignition ON, observe the drivers window, while pressing and releasing the down switch for the drivers window. The window should roll completely down on command.

CIRCUIT/SYSTEM TESTING
1. Ignition OFF, disconnect the harness connector at the master window switch.
2. Test for less than 1 ohm of resistance between the ground circuit and ground.
- If greater than 1 ohm, test the ground circuit for an open/high resistance.
3. Ignition ON, test for voltage on the voltage circuit to the window switch.
- If no power is present, test the voltage circuit for an open/high resistance.
4. If all circuits test normal, test or replace the master window switch.

COMPONENT TESTING

Drive Window Switch Testing
1. Ignition OFF, disconnect the harness connector at the master window switch.
2. Test for infinite resistance between the voltage supply terminal and the ground terminal with the switch in the rest position.
- If less than infinite resistance, replace the master window switch.
3. Test for less than 2 ohms between the ground terminal and the express function terminal with the switch in the rest position.
- If greater than 2 ohms, replace the master window switch.

REPAIR INSTRUCTIONS
Perform the Diagnostic Repair Verification after completing the diagnostic procedure Verification Tests.
Power Window Switch Replacement