PINPOINT TEST L : The Audio RCU Module Does Not Respond To The Diagnostic Scan Tool
WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Failure to disconnect the battery when instructed will result in false resistance readings. Refer to
Battery, Mounting and Cables
.
- L1 CHECK THE AUDIO RCU MODULE VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Disconnect: Audio RCU module C3077 .
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C3077-1 Ground
Is the voltage greater than 11 volts?
Yes GO to L2. No VERIFY the BCM fuse 2 (15A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the OEM Electrical Wiring Diagram Introduction to identify the possible causes of the circuit short. - L2 CHECK THE AUDIO RCU MODULE GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure:
Positive Lead Measurement / Action Negative Lead C3077-4 Ground
Is the resistance less than 3 ohms?
Yes CONNECT the negative battery cable. GO to L3. No REPAIR the circuit. - L3 CHECK THE I-CAN CIRCUITS BETWEEN THE AUDIO RCU MODULE AND THE IPC FOR AN OPEN
- Disconnect: IPC C220 .
- Measure:
4.2-Inch Display
Positive Lead Measurement / Action Negative Lead C3077-2 C220-12 C3077-3 C220-13 8-Inch Touchscreen
Positive Lead Measurement / Action Negative Lead C3077-2 C220-25 C3077-3 C220-26
Are the resistances less than 3 ohms?
Yes GO to L4. No REPAIR the circuit in question. - L4 CHECK FOR CORRECT AUDIO RCU MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect the audio RCU module connector and related in-line connectors.
- Repair:
- corrosion (replace connector or terminals - clean module pins)
- damaged or bent pins - replace terminals/pins
- pushed-out pins - replace pins as necessary
- Reconnect the audio RCU module connector and related in-line connectors. Make sure they seat and latch 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 audio RCU module. Refer to the appropriate Information and Entertainment Systems article for the procedure. No The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.