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Home >> Mercury >> 2008 >> Milan Base, 3.0 1, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 839 (Instrument Cluster System (F250-F550)) >> Diagnostic Tests >> Instrument Cluster (IC) >> Pinpoint Tests >> Pinpoint Test N: The Air Bag Warning Indicator Is Never/Always On >> Pinpoint Test N: The Air Bag Warning Indicator Is Never/Always On

Pinpoint Test N: The Air Bag Warning Indicator Is Never/Always On

WARNING: This page is about a different car, the 2007 Ford Pickup, 2007 Ford F550 Super Duty, 2007 Ford F450 Super Duty, and 2007 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION: Use the correct probe adaptor(s) when making measurements. Failure to use the correct probe adaptor(s) may damage the connector.
  1. N1 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND RCM SELF-TESTS 
    • Check for recorded RCM DTCs from both the continuous and on-demand self-tests.
    • Are any RCM DTCs recorded? 
    1. YES  : For DTC B1869, go to  N5 .

      For DTC B1870, go to  N3 .

      For all other RCM DTCs, REFER to SUPPLEMENTAL RESTRAINT SYSTEM article.

    2. NO  : Go to  N2.
  2. N2 ISOLATE THE AIR BAG MODULE 
    • Key in OFF position.
    • Deactivate the supplemental restraint system (SRS). Refer to SUPPLEMENTAL RESTRAINT SYSTEM article.
    • Disconnect: RCM C2041
    • Observe the air bag warning indicator.
    • Key in ON position.
    • Does the air bag warning indicator illuminate? 
    1. YES  : Go to  N8.
    2. NO  : Go to  N7.
  3. N3 CHECK THE RCM FOR A SHORT TO VOLTAGE 
    • Deactivate the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM article.
    • Key in OFF position.
    • Disconnect: Instrument Cluster C220A
    • Key in ON position.
    • Enter the following diagnostic mode on the diagnostic tool: RCM Self-Test
      • NOTE: It is normal for DTC B1869 to be present when carrying out this step and should be ignored.
    • Clear the continuous and on-demand DTCs. Repeat the RCM continuous and on-demand self-tests.
    • Is DTC B1870 retrieved? 
    1. YES  : Go to  N4.
    2. NO  : Go to  N7.
  4. N4 CHECK CIRCUIT 608 (BK/YE) FOR A SHORT TO VOLTAGE 
    • Key in OFF position.
    • Disconnect: RCM C2041
    • Key in ON position.
      • Fig 1: Checking Circuit For Voltage
      GF0005429Courtesy of FORD MOTOR CO.
    • Measure the voltage between the instrument cluster C220a-14, circuit 608 (BK/YE), harness side and ground.
    • Is voltage present? 
    1. YES  : REPAIR the circuit. TEST the system for normal operation.

      REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the self-test.

    2. NO  : Go to  N8.
  5. N5 CHECK CIRCUIT 608 (BK/YE) FOR AN OPEN 
    • Key in OFF position.
    • Deactivate the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM article.
    • Disconnect: RCM C2041
    • Disconnect: Instrument Cluster C220a
      • Fig 2: Checking Circuit For Open
      GF0008180Courtesy of FORD MOTOR CO.
    • Measure the resistance between the instrument cluster C220a-14, circuit 608 (BK/YE), harness side and the RCM C2041-20, circuit 608 (BK/YE) harness side.
    • Is the resistance less than 5 ohms? 
    1. YES  : Go to  N6.
    2. NO  : REPAIR the circuit. REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  6. N6 CHECK CIRCUIT 608 (BK/YE) FOR A SHORT TO GROUND 
    • Key in OFF position.
    • Disconnect: Instrument Cluster C220A
      • Fig 3: Checking Circuit For Short To Ground
      GF0005427Courtesy of FORD MOTOR CO.
    • Measure the resistance between the instrument cluster C220a-14, circuit 608 (BK/YE), harness side and ground.
    • Is the resistance greater than 10,000 ohms? 
    1. YES  : Go to  N7.
    2. NO  : REPAIR the circuit. TEST the system for normal operation.

      REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the self-test.

  7. N7 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION 
    • Disconnect all the instrument cluster connectors.
    • Check for:
      • corrosion
      • damaged pins
      • 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? 
    1. YES  : INSTALL a new instrument cluster. REFER to Instrument Cluster (IC) .

      ACTIVATE the air bag system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. TEST the system for normal operation.

    2. NO  : The system is operating correctly at this time. ACTIVATE the air bag system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  8. N8 CHECK FOR CORRECT RCM OPERATION 
    • Disconnect all the RCM connectors.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect all the RCM connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    1. YES  : INSTALL a new RCM. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article.

      REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. TEST the system for normal operation.

    2. NO  : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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