Pinpoint Test F: The One-Touch Up/Down Feature is Inoperative - LF

Glass, Frames and Mechanisms

Pinpoint Test F: The One-Touch Up/Down Feature is Inoperative - LF

Refer to Wiring Diagram Set 100, Power Windows for schematic and connector information Electrical Diagrams.

Normal Operation

Under normal operation, the LF power window motor microprocessor receives power at all times through circuit SBP01 (RD) and from the accessory delay relay through circuit CBP41 (BU). Ground is provided at all times through circuit GD143 (BK/VT). The master window control switch provides voltage input to the power window motor microprocessor through circuit CPW10 (YE/VT) to operate the driver window down, and voltage input through circuit CPW11 (BU/GY) to operate the driver window up. To operate the one-touch feature, the master window control switch provides a ground input to the LF power window motor microprocessor through circuit CPW29 (VT/GY) in addition to the up or down request.

This pinpoint test is intended to diagnose the following:

- Fuse(s)

- Wiring, terminals or connectors

- Window control switch

PINPOINT TEST F : THE ONE-TOUCH UP/DOWN FEATURE IS INOPERATIVE - LF

NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

F1 CHECK FOR POWER (B+) LOSS DURING LF WINDOW OPERATION

- Verify if power (B+) was lost during LF window operation.

Was power (B+) lost while LF window was in operation?

Yes
LOWER the LF window to the full OPEN position. MAKE SURE the window glass stalls in the full DOWN position for at least a half second. Normal functionality should resume. TEST the system for normal operation.

No
GO to F2.

F2 INITIALIZE THE LF MOTOR

- Carry out the LF window motor initialization procedure. Refer to Window Motor Initialization .

Are the one-touch up/down functions operating correctly?

Yes
Repair is complete. TEST the system for normal operation.

No
GO to F3.

F3 CHECK THE MASTER WINDOW CONTROL SWITCH

- Carry out the front window switch component test.

Did the front window switch pass the component test?

Yes
For Expedition, GO to F4.

For Navigator, GO to F5.

No
INSTALL a new master window control switch. REFER to Window Control Switch . TEST the system for normal operation.

F4 CHECK THE FRONT WINDOW SWITCH TO LF MOTOR FEEDS

- Ignition OFF.

- Open the front door to disable delayed accessory power.

- Disconnect: Master Power Window Control Switch C504A.

- Disconnect: LF Power Window Motor C540.

- Measure the resistance between LF power window motor C540, harness side and master window control switch C504A, harness side using the following chart:

LF Power Window Motor Circuit Master Window Control Switch C540-7 CPW11 (BU/GY) C504A-5 C540-4 CPW10 (YE/VT) C504A-1 C540-6 CPW29 (VT/GY) C504A-7

Is the resistance less than 5 ohms?

Yes
GO to F6.

No
REPAIR circuit CPW11 (BU/GY), CPW10 (YE/VT) or CPW29 (VT/GY) for an open. DE-INITIALIZE, then INITIALIZE the LF power window motor. REFER to Window Motor Initialization . TEST the system for normal operation.

F5 CHECK THE FRONT WINDOW SWITCH TO LF MOTOR FEEDS

- Ignition OFF.

- Open the front door to disable delayed accessory power.

- Disconnect: Master Power Window Control Switch C535A.

- Disconnect: LF Power Window Motor C540.

- Measure the resistance between LF power window motor C540, harness side and master window control switch C535A, harness side using the following chart:

LF Power Window Motor Circuit Master Window Control Switch C540-7 CPW11 (BU/GY) C535A-4 C540-4 CPW10 (YE/VT) C535A-7 C540-6 CPW29 (VT/GY) C535A-8

- Wiggle the harness while measuring the resistances.

Is the resistance less than 5 ohms?

Yes
GO to F7.

No
REPAIR circuit GD143 (BK/VT) for an open. DE-INITIALIZE, then INITIALIZE the LF power window motor. REFER to Window Motor Initialization . TEST the system for normal operation.

F7 CHECK FOR INTERMITTENT POWER CONNECTIONS

- Ignition ON.

- Measure the voltage between LF power window motor C540-3, circuit SBP01 (RD), harness side and ground; and between C540-2, circuit CPB41 (BU), harness side and ground.

- Wiggle the harness while measuring the voltages.

Is the voltage greater than 10 volts?

Yes
INSTALL a new LF power window motor. REFER to Window Regulator Motor - Front Door . INITIALIZE the LF power window motor. REFER to Window Motor Initialization . TEST the system for normal operation.

No
VERIFY Smart Junction Box (SJB) fuses 1 (30A) and 41 (15A) are OK. If OK, REPAIR circuit SBP01 (RD) or CPB41 (BU) for an open. DE-INITIALIZE, then INITIALIZE the LF power window motor. REFER to Window Motor Initialization . TEST the system for normal operation.

If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams. REPAIR the circuit. DE-INITIALIZE, then INITIALIZE the LF power window motor. REFER to Window Motor Initialization . TEST the system for normal operation.