SECTION 501-12: Instrument Panel and Console
2014 Flex Workshop Manual
DIAGNOSIS AND TESTING
Procedure revision date: 05/02/2013

Refrigerator


Special Tool(s)
Flex Probe Kit
NUD105-R025D or equivalent

Refrigerator Diagnostic Mode

The refrigerator can be switched into a diagnostic mode to read potential on-demand error codes generated by the Compressor Driver Module. When the refrigerator is in diagnostic mode, the FREEZE LED on the refrigerator switch will flash 1-5 times, depending on the error. Perform the following steps in order to access the refrigerator diagnostic mode:

  1. Ignition ON.
  1. Press the refrigerator switch to the COOL position for approximately 1 second, until the COOL LED illuminates.
  1. Press the refrigerator switch again to the COOL position for approximately 5 seconds, until the COOL LED flashes quickly and repeatedly.

  1. NOTE: Use the Diagnostic Mode Error Code Chart to determine the error.

    When the COOL LED is quickly flashing, the FREEZE LED will display the error code by flashing 1-5 times, depending on the error.

  1. NOTE: If the refrigerator is in diagnostic mode and the ignition is turned OFF, the refrigerator will restart in COOL mode when the ignition is turned back ON.

    To exit diagnostic mode, press the refrigerator switch to the COOL position for approximately 1 second. The COOL LED will stop flashing, but will remain illuminated, and the refrigerator will be in COOL mode.


 Diagnostic Mode Error Code Chart

Number of Flashes Diagnostic Error Code Diagnostic Error Code Description Action
1 Battery protection cut-out The voltage supply is below the parameter settings. This code may set when the refrigerator has been active with the engine off. START the engine and retest. If a concern is still present, GO to Pinpoint Test A .
2 Fan over-current cut-out The condenser cooling fan loads the compressor driver module with more than 1 peak amp. CHECK the console vents, compressor compartment, and condenser for dust collection and/or debris. CHECK the condenser cooling fan for binding and make sure it is free of debris. CLEAN as necessary. INSPECT the condenser cooling fan wiring. TEST for normal operation with the engine running. If a concern is found with the fan or wiring, INSTALL a new refrigerator assembly. REFER to Refrigerator . If a concern was not found with the fan or wiring and error code 2 is still present after cleaning, INSTALL a new compressor driver module. REFER to Compressor Driver Module .
3 Motor start error The rotor is blocked or the differential pressure in the refrigeration system is too high (greater than 75.2 psi / 5 bar). This may occur in high ambient temperature situations. This may also result from the refrigerator being turned off and on within a short period of time while a high load/ambient temperature is present. TURN the refrigerator off. WAIT 15 minutes for the system to release the differential pressure. TEST for normal operation with the engine running. If the concern is still present, INSTALL a new refrigerator assembly. REFER to Refrigerator .
4 Minimum motor speed error The compressor motor cannot maintain a minimum speed of 1,850 rpm due to high cooling load or high ambient temperatures. Continuous compressor operation during high ambient temperatures may also cause this concern. TURN the refrigerator off. WAIT 15 minutes for the refrigerator to cool down. TEST for normal operation with the engine running. If the concern is still present, INSTALL a new refrigerator assembly. REFER to Refrigerator .
5 Thermal cut-out of electronic unit (compressor driver module) The compressor driver module has exceeded the maximum temperature limit due to high cooling load or high ambient temperatures. TURN the refrigerator off. WAIT 15 minutes for the compressor driver module to cool down. CHECK the console vents, compressor compartment, and condenser for dust collection and/or debris. CHECK the condenser cooling fan for binding and make sure it is free of debris. CLEAN as necessary. INSPECT the condenser cooling fan wiring. TEST for normal operation with the engine running. If a concern is found with the fan or wiring, INSTALL a new refrigerator assembly. REFER to Refrigerator . If a concern was not found with the fan or wiring and error code 5 is still present after cleaning, INSTALL a new compressor driver module. REFER to Compressor Driver Module .

 

Symptom Chart(s)

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Section 100-00 for information about these diagnostic practices.

 
Symptom Chart
Condition Possible Sources Action
  • The refrigerator is inoperative/does not operate correctly and no flash codes are present
  • Blockage or debris
  • Compressor driver module
  • Fuse(s)
  • Refrigerator controller circuit board
  • Refrigerator assembly
  • Refrigerator switch
  • Run/start relay
  • Wiring, terminals or connectors
  • CHECK the console vent for blockage or debris. CLEAN as necessary and RETEST. If concern remains, GO to Pinpoint Test A .
 

Pinpoint Tests

 

Pinpoint Test A: The Refrigerator Is Inoperative/Does Not Operate Correctly

Refer to Wiring Diagrams Cell 105 , Refrigerated Console for schematic and connector information.

Diagnostic Overview

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Section 100-00 for information about these practices.

Normal Operation and Fault Conditions

Refer to Refrigerator .



Signal Circuit Color Circuit Function
C BU Acts as the signal ground for the other signal circuits (BN-signal P, GY-signal T, and YE-signal D)
P BN Supplies reference voltage to the compressor driver module from the refrigerator controller circuit board.

Used to determine the under voltage shut down threshold of the compressor driver module.
T GY Determines the rotation speed of the compressor.

Controls compressor cycling.
D YE Transfers the compressor driver module pulse error code(s) to the refrigerator controller circuit board. The refrigerator controller circuit board outputs the error code(s) to the refrigerator switch LED.

Two circuits between the compressor driver module and compressor supply the 2 phase compressor motor with PWM voltage. The third circuit provides a switched ground signal.

Under normal conditions, voltage must be at least 12.6 volts for the compressor to turn on. The refrigerator controller circuit board is equipped with a battery monitor to prevent the vehicle battery from discharging completely. If the refrigerator is operated at a voltage above 12.6 volts and the battery voltage decreases, the compressor will shut off when the voltage reaches 11.5 volts ± .3 volts. In order for the compressor to switch on again after being switched off by the battery monitor, voltage must be returned to a minimum of 12.9 volts.

 
PINPOINT TEST A: THE REFRIGERATOR IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

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.

Test Step Result / Action to Take
  A1 CHECK REFRIGERATOR CONTROLLER CIRCUIT BOARD POWER SUPPLY CIRCUIT FOR VOLTAGE  

    NOTE: Most connections on the refrigerator controller circuit board are separate blade terminals.

  • Ignition OFF.
  • Disconnect: Refrigerator Controller Circuit Board Power Supply (RD B+).
  • Start the engine.
  • Measure the voltage between the refrigerator controller circuit board power supply circuit (RD B+), harness side and ground.
  • Is the voltage greater than 12.9 volts?
Yes
GO to A2 .

No
VERIFY that BCM fuse 37 (10A) is OK. If OK, REPAIR refrigerator controller circuit board power supply circuit (RD B+) or circuit CBP37 (WH). TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams manual to identify the possible causes of the circuit short. REPAIR the circuit. TEST the system for normal operation.
  A2 CHECK REFRIGERATOR CONTROLLER CIRCUIT BOARD GROUND CIRCUIT FOR AN OPEN  
  • Ignition OFF.
  • Disconnect: Refrigerator Controller Circuit Board Ground (BK GND).
  • Start the engine.
  • Measure the voltage between the refrigerator controller circuit board power supply circuit (RD B+), harness side, and the refrigerator controller circuit board ground circuit (BK GND), harness side.
  • Is the voltage greater than 12.9 volts?
Yes
GO to A3 .

No
REPAIR refrigerator controller circuit board ground circuit (BK GND) or circuit GD349 (BK/GY). TEST the system for normal operation.
  A3 CHECK THE REFRIGERATOR SWITCH  
  • Remove the refrigerator switch. REFER to Refrigerator Switch .
  • Carry out the Refrigerator Switch component test in this section.
  • Did the refrigerator switch pass the component test?
Yes
GO to A4 .

No
INSTALL a new refrigerator switch. REFER to Refrigerator Switch .
  A4 CHECK REFRIGERATOR CONTROLLER CIRCUIT BOARD TERMINAL FOR VOLTAGE OUTPUT TO COMPRESSOR DRIVER MODULE  
  • Ignition OFF.
  • Connect: Refrigerator Controller Circuit Board Power Supply (RD B+) And Ground (BK GND).
  • Disconnect: Refrigerator Controller Circuit Board Power Supply To Compressor Driver Module (RD+).
  • Start the engine.
  • Measure the voltage between the refrigerator controller circuit board terminal for the Compressor Driver Module power circuit (RD+), component side and ground.
  • Is the voltage greater than 12.9 volts?
Yes
GO to A5 .

No
GO to A11 .
  A5 CHECK REFRIGERATOR CONTROLLER CIRCUIT BOARD TERMINAL FOR GROUND SUPPLY FOR THE COMPRESSOR DRIVER MODULE  
  • Ignition OFF.
  • Disconnect: Refrigerator Controller Circuit Board Ground Supply To Compressor Driver Module (BK-).
  • Start the engine.
  • Measure the voltage between the refrigerator controller circuit board terminal for the compressor driver module ground circuit (BK-), component side and the refrigerator controller circuit board terminal for the compressor driver module power circuit (RD+), component side.
  • Is the voltage greater than 12.9 volts?
Yes
GO to A6 .

No
GO to A11 .
  A6 CHECK COMPRESSOR DRIVER MODULE POWER CIRCUIT FOR VOLTAGE  
  • Ignition OFF.
  • Connect: Refrigerator Controller Circuit Board Power Supply To Compressor Driver Module (RD+) And Refrigerator Controller Circuit Board Ground Supply To Compressor Driver Module (BK-).
  • Disconnect: Compressor Driver Module Power Supply (RD+) And Compressor Driver Module Ground Supply (BK-).
  • Start the engine.
  • Measure the voltage between the compressor driver module power circuit (RD+), harness side and ground.
  • Is the voltage greater than 12.9 volts?
Yes
GO to A7 .

No
REPAIR compressor driver module power circuit (RD+). TEST the system for normal operation.
  A7 CHECK COMPRESSOR DRIVER MODULE GROUND CIRCUIT FOR AN OPEN  
  • Measure the voltage between the compressor driver module power circuit (RD+), harness side, and the compressor driver module ground circuit (BK-), harness side.
  • Is the voltage greater than 12.9 volts?
Yes
GO to A8 .

No
REPAIR the compressor driver module ground circuit (BK-). TEST the system for normal operation.
  A8 CHECK THE CONTROL CIRCUITS FOR A SHORT TO VOLTAGE  
  • Ignition OFF.
  • Disconnect: Compressor Driver Module YE (Signal D), BU (Signal C), BN (Signal P), And GY (Signal T).
  • Disconnect: Refrigerator Controller Circuit Board BU (Signal Ground), BN (Under Voltage Sense/Vref), GY (Compressor Run/Stop, Rotation Speed Sense), And YE (Error Code).
  • Ignition ON.
  • Measure the voltage between the compressor driver module circuits, harness side and ground.


    • Positive Lead Circuit Negative Lead Circuit
    Signal D YE Ground YE
    Signal C BU Ground BU
    Signal P BN Ground BN
    Signal T GY Ground GY



  • Is any voltage present?
Yes
REPAIR the circuit in question. TEST the system for normal operation.

No
GO to A9 .
  A9 CHECK THE CONTROL CIRCUITS FOR AN OPEN OR SHORT TO GROUND  
  • Ignition OFF.
  • Measure the resistance between the compressor driver module, harness side and the refrigerator controller circuit board, harness side; and between the compressor driver module, harness side and ground.


    • Positive Lead Circuit Negative Lead Circuit
    Signal D YE Refrigerator controller circuit board error code YE
    Signal D YE Ground YE
    Signal C BU Refrigerator controller circuit board signal ground BU
    Signal C BU Ground BU
    Signal P BN Refrigerator controller circuit board under voltage sense/Vref BN
    Signal P BN Ground BN
    Signal T GY Refrigerator controller circuit board compressor run/stop, rotation speed sense GY
    Signal T GY Ground GY



  • Are the resistances less than 3 ohms between the compressor driver module and the refrigerator controller circuit board, and greater than 10,000 ohms between the compressor driver module and ground?
Yes
GO to A10 .

No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.
  A10 CHECK FOR CORRECT COMPRESSOR DRIVER MODULE AND COMPRESSOR OPERATION  
  • Disconnect all the compressor driver module and compressor connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean circuit board pins)
    • damaged pins (install new terminals or pins)
    • pushed out pins (install new pins as necessary)
  • Connect all the compressor driver module and compressor 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 compressor driver module. REFER to Compressor Driver Module . TEST the system for normal operation. If the concern is still present, INSTALL a new refrigerator assembly. REFER to Refrigerator .

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.
  A11 CHECK FOR CORRECT REFRIGERATOR CONTROLLER CIRCUIT BOARD OPERATION  
  • Ignition OFF.
  • Disconnect all the refrigerator controller circuit board connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean circuit board pins)
    • damaged pins (install new terminals or pins)
    • pushed out pins (install new pins as necessary)
  • Connect all the refrigerator controller circuit board connectors and make sure they seat correctly.
  • Operate the system and verify the concern is still present.
  • Is the concern still present?
Yes
CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new refrigerator assembly. REFER to Refrigerator .

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
 

Component Tests

 

Refrigerator Switch



Connect Self-Powered Test Light Or Ohmmeter To Terminals Move Refrigerator Switch To This Position A Good Refrigerator Switch Will Indicate
1 and 2 COOL Closed
1 and 3 — Open
1 and 4 — Open
1 and 5 — Open
1 and 6 FREEZE Closed
2 and 3 — Open
2 and 4 — Open
2 and 5 — Open
2 and 6 — Open
3 and 4 — Open
3 and 5 — Open
3 and 6 — Open
4 and 5 — Open
4 and 6 — Open
5 and 6 — Open