Pinpoint Test W : The DSP (Audio Digital Signal Processing Module) Does Not Respond To The Diagnostic Scan Tool
WARNING: This page is about a different car, the 2018 Lincoln Continental. However, it is still accessible from the selected car via links, so may be relevant.
- W1 CHECK THE AUDIO DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Audio DSP C4326C (Revel Audio) or C4366C (Revel Ultima)
- Ignition ON.
- Measure:
Revel Audio System
Positive Lead Measurement / Action Negative Lead C4326C-4 Ground C4326C-8 Ground Revel Ultima Audio System
Positive Lead Measurement / Action Negative Lead C4366C-6 Ground C4366C-12 Ground
Are the voltages greater than 11 volts?
Yes GO to W2 No VERIFY BCM fuse 28 (20A) or fuse 5 (20A) is OK. If OK, REPAIR the circuit. If not OK, REFER to OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short. - W2 CHECK THE AUDIO DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure:
Revel Audio System
Positive Lead Measurement / Action Negative Lead C4326C-1 Ground C4326C-5 Ground Revel Ultima Audio System
Positive Lead Measurement / Action Negative Lead C4366C-3 Ground C4366C-9 Ground
Are the resistances less than 3 ohms?
Yes GO to W3 No REPAIR the circuit. - W3 CHECK THE HS-CAN3 (HIGH SPEED-CONTROLLER AREA NETWORK 3) CIRCUITS BETWEEN THE AUDIO DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN
- Disconnect: GWM C2803 .
- Measure:
Revel Audio System
Positive Lead Measurement / Action Negative Lead C4326C-2 C2803-16 C4326C-3 C2803-15 Revel Ultima Audio System
Positive Lead Measurement / Action Negative Lead C4366C-4 C2803-16 C4366C-5 C2803-15
Are the resistances less than 3 ohms?
Yes GO to W4 No REPAIR the circuit in question. - W4 CHECK FOR CORRECT AUDIO DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect the audio DSP connector and related in-line connectors.
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Reconnect the audio DSP connector and related in-line connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new audio DSP. For Revel Audio, Refer to: Audio Digital Signal Processing (DSP) Module - Vehicles With: Harman Revel Audio System . For Revel Ultima, REFER to: Audio Digital Signal Processing (DSP) Module - Vehicles With: Harman Revel Ultima Audio System . No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.