Hands Free Module (Hfm) - Electrical Diagnostics: Other RAM Pickup 2500

When Monitored

With the ignition on.

Set Condition

The Hands Free Module (HFM) detects a short to ground or open on the (X712) Microphone 1 IN (+) circuit.

Possible Causes

Scheme 173

Scheme 174

Scheme 175

1. CHECK FOR ACTIVE DTC NOTE: Verify the connection of the Rearview Mirror harness connector. Turn the ignition on. With the scan tool, read the active DTCs. Does the scan tool display this DTC as active? Yes Go To 2 . No If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
2. INSIDE REARVIEW MIRROR Turn the ignition off. Disconnect the Inside Rearview Mirror harness connector. Connect a jumper wire between the (X793) Microphone Feed and the (X712) Microphone 1 IN (+) circuits. Turn the ignition on. With the scan tool, read the DTCs. Does the scan tool display this DTC as active? Yes Go To 3 . No Replace the Inside Rearview Mirror in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
3. (X712) MICROPHONE 1 IN (+) CIRCUIT OPEN Turn the ignition off. Disconnect the Hands Free Module harness connector. Measure the resistance of the (X712) Microphone 1 IN (+) circuit between the Inside Rearview Mirror and Hands Free Module 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»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500. No Go To 4 .
4. (X712) MICROPHONE 1 IN (+) CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the Hands Free Module harness connector. 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»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500. No Replace the Hands Free Module in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.

B143C-MICROPHONE 1 CIRCUIT HIGH

For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article .

With the ignition on.

The Hands Free Module (HFM) detects a short to voltage on the (X712) Microphone 1 IN (+) circuit.

Scheme 176

1. CHECK FOR ACTIVE DTC NOTE: Verify the connection of the Rearview Mirror harness connector. Turn the ignition on. With the scan tool, read the active DTCs. Does the scan tool display this DTC as active? Yes Go To 2 . No If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
2. INSIDE REARVIEW MIRROR Turn the ignition off. Disconnect the Rearview Mirror C2 harness connector. Turn the ignition on. With the scan tool, read the active DTCs. Does the scan tool display this DTC as active? Yes Go To 3 . No Replace the Rearview Mirror in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
3. (X712) MICROPHONE 1 IN (+) CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the Hands Free Module harness connector. Turn the ignition on. Measure the voltage of the (X712) Microphone circuit. Is the voltage above 1.0 volt? Yes Repair the (X712) Microphone circuit for a short to voltage. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500. No Replace the Hands Free Module in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.

B143E-MICROPHONE 2 CIRCUIT LOW

For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article .

With the ignition on.

The Hands Free Module (HFM) detects a short to ground or open on the (X722) Microphone 2 IN (+) circuit.

Scheme 177

Scheme 178

Scheme 179

1. CHECK FOR ACTIVE DTC NOTE: Verify the connection of the Rearview Mirror harness connector. Turn the ignition on. With the scan tool, read the active DTCs. Does the scan tool display this DTC as active? Yes Go To 2 . No If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
2. INSIDE REARVIEW MIRROR Turn the ignition off. Disconnect the Inside Rearview Mirror harness connector. Connect a jumper wire between the (X793) Microphone Feed and the (X722) Microphone 2 IN (+) circuits. Turn the ignition on. With the scan tool, read the DTCs. Does the scan tool display this DTC as active? Yes Go To 3 . No Replace the Inside Rearview Mirror in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
3. (X722) MICROPHONE 2 IN (+) CIRCUIT OPEN Turn the ignition off. Disconnect the Hands Free Module harness connector. Measure the resistance of the (X722) Microphone 2 IN (+) circuit between the Inside Rearview Mirror and Hands Free Module harness connectors. Is the resistance above 10K Ohms? Yes Repair the (X722) Microphone 2 IN (+) circuit for an open. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500. No Go To 4 .
4. (X722) MICROPHONE 2 IN (+) CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the Hands Free Module harness connector. Measure the resistance between ground and the (X722) Microphone 2 IN (+) circuit. Is the resistance below 10K Ohms? Yes Repair the (X722) Microphone 2 IN (+) circuit for short to ground. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500. No Replace the Hands Free Module in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.

B143F-MICROPHONE 2 CIRCUIT HIGH

For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article .

With the ignition on.

The Hands Free Module (HFM) detects a short to voltage on the (X722) Microphone 2 IN (+) circuit.

Scheme 180

1. CHECK FOR ACTIVE DTC NOTE: Verify the connection of the Rearview Mirror harness connector. Turn the ignition on. With the scan tool, read the active DTCs. Does the scan tool display this DTC as active? Yes Go To 2 . No If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
2. INSIDE REARVIEW MIRROR Turn the ignition off. Disconnect the Rearview Mirror C2 harness connector. Turn the ignition on. With the scan tool, read the active DTCs. Does the scan tool display this DTC as active? Yes Go To 3 . No Replace the Rearview Mirror in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.
3. (X722) MICROPHONE CIRCUITS SHORTED TO VOLTAGE Turn the ignition off. Disconnect the Hands Free Module harness connector. Turn the ignition on. Measure the voltage of the (X722) Microphone circuit. Is the voltage above 1.0 volt? Yes Repair the (X722) Microphone circuit for a short to voltage. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500. No Replace the Hands Free Module in accordance with the Service Information. Perform the BODY VERIFICATION TEST. Refer to «BODY VERIFICATION TEST»(ref-457926-S40044966262012030200000) for 1500, 2500 and «BODY VERIFICATION TEST»(ref-457927-S20352278932012030200000) 3500 or 3500 Cab and Chassis, 4500 and 5500.

Continuously when the ignition is on.

Battery voltage between 10 and 16 volts.

Ignition Off Draw (IOD) fuse installed.

The controller detects a short to ground on the CAN Interior Bus (125K) (+) circuit or a short to voltage on the CAN Interior Bus (125K) (-) circuit.

Continuously when the ignition is on.

The battery voltage between 10.0 and 16.0 Volts.

Ignition Off Draw (IOD) fuse installed.

Totally Integrated Power Module (TIPM) is configured correctly.

Bus messages not received from the Totally Integrated Power Module (TIPM) for approximately two to five seconds.

Continuously when the ignition is on.

The battery voltage is between 10 and 16 volts.

Ignition Off Draw (IOD) fuse installed.

Totally Integrated Power Module (TIPM) is configured correctly.

Bus messages not received from the Instrument Cluster (CCN) for approximately two to five seconds.

Continuously when the ignition is on.

Battery voltage between 10 and 16 volts.

Ignition Off Draw (IOD) fused installed.

Totally Integrated Power Module (TIPM) is configured correctly.

Bus messages not received from the Radio for approximately two to five seconds.