Pinpoint Test R : The DSP (Audio Digital Signal Processing Module) Does Not Respond To The Diagnostic Scan Tool

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Refer to MODULE COMMUNICATIONS NETWORK for schematic and connector information. Refer to AUDIO SYSTEM/NAVIGATION - WITH HARMAN REVEL for schematic and connector information.
Normal Operation and Fault Conditions

The DSP communicates on the HS-CAN3.

Possible Sources
- Fuse
- Wiring, terminals and connector
- DSP
Visual Inspection and Pre-checks
- Verify BJB fuses 136 (20A) and 137 (20A) are OK.

R1 CHECK THE DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

Ignition OFF.

Disconnect: DSP C4452C.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4452C-4	Courtesy of FORD MOTOR COMPANY	Ground
C4452C-8	Courtesy of FORD MOTOR COMPANY	Ground

Are the voltages greater than 11 volts?

Yes

GO to R2

No	VERIFY BJB fuse 136 (20A) or 137 (20A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short.

R2 CHECK THE DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) GROUND CIRCUITS FOR AN OPEN

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4452C-1	Courtesy of FORD MOTOR COMPANY	Ground
C4452C-5	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances less than 3 ohms?

Yes

GO to R3

No	REPAIR the circuit in question.

R3 CHECK THE HS-CAN3 (HIGH-SPEED CONTROLLER AREA NETWORK 3) CIRCUITS BETWEEN THE DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN

Disconnect: GWM C2431.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4452C-2	Courtesy of FORD MOTOR COMPANY	C2431-16
C4452C-3	Courtesy of FORD MOTOR COMPANY	C2431-15

Are the resistances less than 3 ohms?

Yes

GO to R4

No	REPAIR the circuit in question.

R4 CHECK FOR CORRECT DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) OPERATION

Ignition OFF.

Disconnect and inspect all the DSP 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 DSP 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 service articles: TSB, General Service Bulletin (GSB), SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new DSP. REFER to: Audio Digital Signal Processing (DSP) Module .

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.