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Diagnostic Test

WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR ACTIVE DTC 
    NOTE:

    Verify the connection of the Inside Rearview Mirror harness connector.

    1. Turn the ignition on.
    2. With the scan tool, read the active DTC's.

      Does the scan tool display B143B-MICROPHONE 1 CIRCUIT LOW as active?

      Yes 

      • Go To  2.

      No 

      • Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  2. CHECK FOR ACTIVE DTC B143E 
    1. With the scan tool, read the active DTC's.

      Does the scan tool display B143E-MICROPHONE 2 CIRCUIT LOW also as active?

      Yes 

      • Go To  3.

      No 

      • Go To  6.
  3. CHECK FOR VOLTAGE AT THE INSIDE REARVIEW MIRROR 
    Fig 1: Measuring Voltage Between Microphone Feed Circuit & Ground
    GC0091268Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Inside Rearview Mirror harness connector.
    3. Turn the ignition on.
    4. Measure the voltage between the (X793) Microphone Feed circuit and ground.

      Is the voltage above 10.0 volts?

      Yes 

      • Go To  6.

      No 

      • Go To  4.
  4. CHECK FOR VOLTAGE AT THE RADIO 
    Fig 2: Checking Microphone Feed Circuit For Voltage At Radio
    GC0091269Courtesy of CHRYSLER GROUP, LLC
    1. While back probing, measure the voltage between the (X793) Microphone Feed circuit and ground at the Radio C2 harness connector.
      NOTE:

      The graphic shows the connector for reference only. Back probe the harness connector.

      Is the voltage above 10.0 volts?

      Yes 

      • Repair the (X793) Microphone Feed circuit for an open.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  5.
  5. RESTORE THE VEHICLE CONFIGURATION 
    1. With the scan tool, restore the vehicle configuration.
    2. Turn the ignition off, then back on.
    3. With the scan tool, read the active DTC's.

      Does the scan tool display B143B-MICROPHONE 1 CIRCUIT LOW as active?

      Yes 

      • Replace the Radio in accordance with the Service Information.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  6. CHECK THE INSIDE REARVIEW MIRROR 
    Fig 3: Checking Inside Rearview Mirror Circuit
    GC0091270Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Inside Rearview Mirror C2 harness connector.
    3. Connect a jumper wire between the (X793) Microphone Feed and the (X712) Microphone 1 IN (+) circuits.
    4. Turn the ignition on.
    5. With the scan tool, read the DTC's.
      NOTE:

      DTC B143C-MICROPHONE 1 CIRCUIT HIGH should display as active as a result of this test.

      Does the scan tool display B143B-MICROPHONE 1 CIRCUIT LOW as active?

      Yes 

      • Go To  7.

      No 

      • Replace the Inside Rearview Mirror in accordance with the Service Information.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  7. CHECK FOR THE (X712) MICROPHONE 1 IN (+) CIRCUIT FOR AN OPEN 
    Fig 4: Checking Microphone 1 In (+) Circuit For An Open
    GC0091271Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Radio C2 harness connector.
    3. Measure the resistance of the (X712) Microphone 1 IN (+) circuit between the Inside Rearview Mirror and Radio C2 harness connectors.

      Is the resistance above 10K Ohms?

      Yes 

      • Repair the (X712) Microphone 1 IN (+) circuit for an open.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Go To  8.
  8. CHECK FOR THE (X712) MICROPHONE 1 IN (+) CIRCUIT FOR A SHORT TO GROUND 
    Fig 5: Checking Microphone 1 In (+) Circuit For A Short To Ground
    GC0091265Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance between ground and the (X712) Microphone 1 IN (+) circuit.

      Is the resistance below 10K Ohms?

      Yes 

      • Repair the (X712) Microphone 1 IN (+) circuit for short to ground.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .

      No 

      • Replace the Radio in accordance with the Service Information.
      • Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .