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

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W1 CHECK THE AUDIO DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: Audio DSP C4348C (Revel® 14-speaker) or C4548C (Revel® 20-speaker).

Ignition ON.

Measure:

Revel® 14-Speaker

Positive Lead	Measurement / Action	Negative Lead
C4348C-4	Courtesy of FORD MOTOR COMPANY	Ground
C4348C-8	Courtesy of FORD MOTOR COMPANY	Ground

Revel® 20-Speaker

Positive Lead	Measurement / Action	Negative Lead
C4548C-6	Courtesy of FORD MOTOR COMPANY	Ground
C4548C-12	Courtesy of FORD MOTOR COMPANY	Ground

Are the voltages greater than 11 volts?

Yes

GO to W2

No	VERIFY BCM fuse 5 (20A) or fuse 28 (20A) is OK. If OK, REPAIR the circuit. If not OK, Refer to the Wiring Diagram Information 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® 14-Speaker

Positive Lead	Measurement / Action	Negative Lead
C4348C-1	Courtesy of FORD MOTOR COMPANY	Ground
C4348C-5	Courtesy of FORD MOTOR COMPANY	Ground

Revel® 20-Speaker

Positive Lead	Measurement / Action	Negative Lead
C4548C-3	Courtesy of FORD MOTOR COMPANY	Ground
C4548C-9	Courtesy of FORD MOTOR COMPANY	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 C2431 .

Measure:

Revel® 14-Speaker

Positive Lead	Measurement / Action	Negative Lead
C4348C-2	Courtesy of FORD MOTOR COMPANY	C2431-16
C4348C-3	Courtesy of FORD MOTOR COMPANY	C2431-15

Revel® 20-Speaker

Positive Lead	Measurement / Action	Negative Lead
C4548C-4	Courtesy of FORD MOTOR COMPANY	C2431-16
C4548C-5	Courtesy of FORD MOTOR COMPANY	C2431-15

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 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 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 audio 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.