Pinpoint Test R: The 4X4 High/Low Range Indicator Is Never/Always On

WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

R1 CARRY OUT THE INSTRUMENT CLUSTER WARNING LAMPS AND CHIME ACTIVE COMMAND USING THE DIAGNOSTIC TOOL
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster Active Command.
- Select the instrument cluster warning lamps and chime active command. Trigger the all lamps active command on and off.
- Observe the 4x4 high and LOW RANGE indicators.
- Does the 4x4 high and LOW RANGE indicators illuminate when triggered on and turn off when triggered off?
- Yes : If the 4x4 indicator is inoperative, GO to R2.
  If the 4x4 indicator is always on, GO to R5.
- No : GO to R10.
R2 CHECK THE 4WD MODULE OPERATION
- Key in OFF position.
- Disconnect: Four-Wheel Drive (4WD) Control Module C281b.
- Connect a fused (10A) jumper wire between the 4WD control module (4x4 high) C281b-12, circuit 210 (LB), harness side and ground; or between the 4WD control module (4x4 low range) C281b-11, circuit 975 (BN/YE), harness side and ground.
  
  Fig 1: Checking 4WD Module Operation
  Courtesy of FORD MOTOR CO.
- Key in ON position.
- Does the 4x4 indicator illuminate?
- Yes : GO to R9.
- No : GO to R3.
R3 CHECK CIRCUIT 210 (LB) OR CIRCUIT 975 (BN/YE) FOR AN OPEN
- Key in OFF position.
- Disconnect: Instrument Cluster C220b.
- Measure the resistance between the instrument cluster (4x4 high) C220b-21, circuit 210 (LB), harness side and the 4WD control module C281b-12, circuit 210 (LB), harness side; or between the instrument cluster (4x4 low range) C220b-22, circuit 975 (BN/YE), harness side and the 4WD control module C281b-11, circuit 975 (BN/YE), harness side.
  
  Fig 2: Checking Circuit 210 (LB) Or Circuit 975 (BN/YE) For Open
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
- Yes : GO to R4.
- No : REPAIR the circuit in question. TEST the system for normal operation.
R4 CHECK CIRCUIT 210 (LB) OR CIRCUIT 975 (BN/YE) FOR A SHORT TO POWER
- If the 4x4 high indicator is inoperative, measure the voltage between the instrument cluster C220b-21, circuit 210 (LB), harness side and ground.
  
  Fig 3: Checking Circuit 210 (LB) Or Circuit 975 (BN/YE) For Short To Power (High Indicator Is Inoperative)
  Courtesy of FORD MOTOR CO.
- If the 4x4 low indicator is inoperative, measure the voltage between the instrument cluster C220b-22, circuit 975 (BN/YE), harness side and ground.
  
  Fig 4: Checking Circuit 210 (LB) Or Circuit 975 (BN/YE) For Short To Power (Low Indicator Is Inoperative)
  Courtesy of FORD MOTOR CO.
- Is any voltage indicated?
- Yes : REPAIR the circuit in question. TEST the system for normal operation.
- No : GO to R10.
R5 CHECK THE VEHICLE CONTENT
- Check the vehicle and determine if it is equipped with a manual shift on the fly system.
- Is the vehicle equipped with a manual shift on the fly system?
- Yes : GO to R6.
- No : GO to R7.
R6 CHECK THE MODE INDICATOR SWITCH
- Disconnect: Mode Indicator Switch C1177.
- Does the indicator continue to illuminate?
- Yes : GO to R7.
- No : INSTALL a new mode indicator switch. REFER to FOUR- WHEEL DRIVE SYSTEMS . TEST the system for normal operation.
R7 CHECK THE 4WD MODULE
- Key in OFF position.
- Disconnect: 4WD Control Module C281b.
- Key in ON position.
- Does the indicator illuminate?
- Yes : GO to R8.
- No : GO to R9.
R8 CHECK CIRCUIT 210 (LB) AND CIRCUIT 975 (BN/YE) FOR A SHORT TO GROUND
- Key in OFF position.
- Disconnect: Instrument Cluster C220b.
- Disconnect: 4WD Control Module C281b.
- If the 4x4 high indicator is inoperative, measure the resistance between the instrument cluster C220b-21, circuit 210 (LB), harness side and ground
  
  Fig 5: Checking Circuit 210 (LB) And Circuit 975 (BN/YE) For Short To Ground (High Indicator Is Inoperative)
  Courtesy of FORD MOTOR CO.
- If the 4x4 low indicator is inoperative, measure the resistance between the instrument cluster C220b-22, circuit 975 (BN/YE), harness side and ground.
  
  Fig 6: Checking Circuit 210 (LB) And Circuit 975 (BN/YE) For Short To Ground (Low Indicator Is Inoperative)
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
- Yes : GO to R10.
- No : REPAIR the circuit in question. TEST the system for normal operation.
R9 CHECK THE FOUR-WHEEL DRIVE (4WD) CONTROL MODULE FOR CORRECT OPERATION
- Disconnect all the 4WD control module connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the 4WD control module connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new 4WD control module. REFER to FOUR- WHEEL DRIVE SYSTEMS . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
R10 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
- Disconnect all the instrument cluster connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the instrument cluster connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new instrument cluster. REFER to INSTRUMENT CLUSTER . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.