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

NOTE: 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. Refer to the OEM WIRING DIAGRAMS COMPONENT TESTING article.
- 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

Fig 1: Measuring Resistance Between LF Power Window Motor C540 And Master Window Control Switch C504A, Harness Side

Courtesy of FORD MOTOR CO.

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

Fig 2: Measuring Resistance Between LF Power Window Motor C540 And Master Window Control Switch C535A, Harness Side

Courtesy of FORD MOTOR CO.

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.

F6 CHECK FOR AN INTERMITTENT GROUND CONNECTION
- Ignition OFF.
- Measure the resistance between LF power window motor C540-8, circuit GD143 (BK/VT), harness side and ground.
  
  Fig 3: Measuring Resistance Between LF Power Window Motor C540-8, Circuit GD143 (BK/VT), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- 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.
  
  Fig 4: Measuring Voltage Between LF Power Window Motor C540-3, Circuit SBP01 (RD), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- 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, refer to SMART JUNCTION BOX (SJB) in OEM FUSE AND RELAY IDENTIFICATION . 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 appropriate OEM WIRING DIAGRAMS article to identify the possible causes of the circuit short.
    
    REPAIR the circuit. DE-INITIALIZE, then INITIALIZE the LF power window motor. REFER to WINDOW MOTOR INITIALIZATION . TEST the system for normal operation.