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Home >> Jeep >> 2021 >> Gladiator Mojave, Part Time T/Case Control, Standard Trans >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> Body Control Module (BCM) - DTCS B16AF-11 To B1792-11 >> DTC Troubleshooting >> B1703-15-Rear Right Fog Lamp Control-Circuit Short To Battery Or Open >> Diagnostic Test
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Diagnostic Test

  1. READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN 
    1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
    2. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
    3. With the scan tool, erase all DTCs.
    4. Turn the ignition off for a minimum of 10.0 seconds.
    5. Turn the ignition on.
    6. Using the recorded Environmental Data and the When Monitored Conditions above, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read Body Control Module (BCM) DTCs.

    Did the DTC return?

    Yes 

    • Go To  2

    No 

    • Perform the appropriate INTERMITTENT CONDITION diagnostic procedure. Refer to STANDARD PROCEDURE .
  2. DISCONNECT THE RIGHT REAR FOG LAMP HARNESS CONNECTOR AND CHECK FOR VOLTAGE ON THE (L898) RIGHT REAR FOG LAMP CIRCUIT 
    NOTE:

    Make sure the Fog Lamps are off when performing this step.

    1. Turn the ignition off.
    2. Disconnect the component harness connector for the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Turn the ignition on.
    4. Using a DVOM, measure the voltage on the circuit being tested at the component harness connector.
    NOTE:

    When probing a circuit at any harness connector, always use an appropriate probing tool to prevent any possible damage to the harness connector terminals.

    Is there any voltage present?

    Yes 

    • Go To  3

    No 

    • Go To  4
  3. DISCONNECT THE BCM HARNESS CONNECTOR(S) AND CHECK THE (L898) RIGHT REAR FOG LAMP CIRCUIT FOR A SHORT TO VOLTAGE 
    1. Turn the ignition off.
    2. Disconnect all Electronic Control Unit (ECU) harness connectors for the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Turn the ignition on.
    4. Using a DVOM, measure the voltage on the circuit being tested at the component harness connector.
    NOTE:

    When probing a circuit at any harness connector, always use an appropriate probing tool to prevent any possible damage to the harness connector terminals.

    Is there any voltage present?

    Yes 

    • Repair the circuit for a short to voltage.
    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

    No 

    • Go To  7
  4. CHECK THE RIGHT REAR FOG LAMP GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE BY LOAD TESTING THE CIRCUIT 
    1. Turn the ignition off.
    2. Connect the positive lead of the load test tool to a 12 volt circuit at the component harness connector.
    3. Connect the negative lead of the load test tool to the ground circuit at the component harness connector (A). Note:  refer to the diagram below.
    4. The bulb on the load test tool should be illuminated and bright if there is no resistance in the circuitry.
    NOTE:

    Note: Why load test a circuit?  A load test is used to determine if a circuit is capable of carrying the amperage needed to perform properly. The 3156 Bulb in the load tool illustrated, is a simple but effective method of testing circuit functionality. A 3156 Bulb has approximately 6.0 Ohms of resistance when the bulb is powered  and draws approximately 2.0 amps of current. Read the CIRCUIT VOLTAGE DROP AND LOAD TESTING PROCEDURES for information on building a simple load test tool and for additional load testing information and alternative methods of load testing or voltage drop testing a circuit. Refer to STANDARD PROCEDURE .

    NOTE:

    Note:  A 12-volt test light can be substituted for the load test tool, but only  if the test light draws enough current to effectively load test the circuit. Many high impedance test lights draw very little amperage (less than 0.1 amps) and are not reliable to load test a circuit. To perform a proper load test of a circuit, the tool being used should draw more than approximately 0.75 amps.

    NOTE:

    Note: Why perform a Voltage Drop Test:  To verify with certainty there is not any resistance in the circuit being tested, perform a simple voltage drop test across the 3156 Bulb of the load test tool. To do so perform the following:

    • 1. Connect the leads of a DVOM to the alligator clips on the load test tool while the load test tool is connected in series with the circuit.
    • 2. Compare the voltage drop across the bulb to the voltage reading across the Battery terminals.
    • 3. The voltage dropped across the bulb should be equal to the voltage reading across the Battery terminals if there is no resistance in the circuit being tested.

    Example:  2.0 Ohms of resistance in the circuit being tested will cause the voltage measurement across the bulb to be 25% less than when compared to Battery voltage. The reason for this is that the 2.0 Ohms in the circuit makes up 25% of the total circuit resistance of 8.0 Ohms. Read the CIRCUIT VOLTAGE DROP AND LOAD TESTING PROCEDURES for information on building a simple load test tool and for additional load testing information and alternative methods of load testing or voltage drop testing a circuit. Refer to STANDARD PROCEDURE .

    GC0174957Courtesy of CHRYSLER GROUP, LLC
    NOTE:

    When probing a circuit at any harness connector, always use an appropriate probing tool to prevent any possible damage to the harness connector terminals.

    NOTE:

    Compare the brightness of the bulb in the load test tool to that of a direct connection to Battery.

    Is the load test bulb illuminated and bright?

    Yes 

    • Go To  5

    No 

    • Repair the ground circuit for an open or high resistance.
    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  5. DISCONNECT THE BCM HARNESS CONNECTOR(S) AND CHECK THE (L898) RIGHT REAR FOG LAMP CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. The ignition must be off when checking the resistance of a circuit.
    2. Disconnect all Electronic Control Unit (ECU) harness connectors containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
    4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
    5. Connect the other lead to the circuit being tested at the ECU harness connector and measure the resistance of the circuit.
    NOTE:

    When probing a circuit at any harness connector, always use an appropriate probing tool to prevent any possible damage to the harness connector terminals.

    Is the resistance above 3.0 Ohms?

    Yes 

    • Repair the circuit for an open or high resistance.
    • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

    No 

    • Go To  6
  6. CONNECT THE BCM HARNESS CONNECTOR(S) - CONNECT A 12-VOLT TEST LIGHT BETWEEN GROUND AND THE (L898) RIGHT REAR FOG LAMP CIRCUIT - CHECK THE BCM OUTPUT 
    1. Connect the Electronic Control Unit (ECU) harness connector(s) for the circuit being tested.
    2. Using a 12-volt test light, connect the test light lead to a known good ground.
    3. With the 12-volt test light, probe the circuit being tested at the component harness connector.
    4. Turn the ignition on.
    5. Activate the system or ECU output for the circuit being tested.
    NOTE:

    When probing a circuit at any harness connector, always use an appropriate probing tool to prevent any possible damage to the harness connector terminals.

    NOTE:

    The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

    Does the test light illuminate brightly?

    Yes 

    No 

    • Go To  7
  7. DISCONNECT RELATED MODULE HARNESS CONNECTIONS AND INSPECT FOR PROBLEMS 
    1. Disconnect all BCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Perform a terminal drag test on each connector terminal to verify proper terminal tension.

      Repair any conditions that are found.

    5. Connect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    10. With the scan tool, read BCM DTCs.

      Did the DTC return?

      Yes 

      No 

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