Pinpoint Test M : The LH Or RH D-Pillar Speaker Is Inoperative

WARNING: This page is about a different car, the 2016 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

M1 CHECK THE AUDIO SIGNAL TO THE SUSPECT D-PILLAR SPEAKER

Ignition OFF.

Disconnect: LH D-Pillar Speaker C4337 .

Disconnect: RH D-Pillar Speaker C4338 .

Ignition ON.

Operate the audio system in radio tuner (AM/FM) mode.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4337-1	Courtesy of FORD MOTOR COMPANY	C4337-3

Positive Lead	Measurement / Action	Negative Lead
C4338-1	Courtesy of FORD MOTOR COMPANY	C4338-3

Is a fluctuating AC voltage present?

Yes	INSTALL a new LH or RH D-pillar speaker.
No	GO to M2.

M2 CHECK THE AUDIO CIRCUITS TO THE SUSPECT D-PILLAR SPEAKER FOR A SHORT TO VOLTAGE

Ignition OFF.

Disconnect: DSP module C4326B .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4337-1	Courtesy of FORD MOTOR COMPANY	Ground
C4337-3	Courtesy of FORD MOTOR COMPANY	Ground

Positive Lead	Measurement / Action	Negative Lead
C4338-1	Courtesy of FORD MOTOR COMPANY	Ground
C4338-3	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit in question.
No	GO to M3.

M3 CHECK THE AUDIO CIRCUITS TO THE SUSPECT D-PILLAR SPEAKER FOR A SHORT TO GROUND

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4337-1	Courtesy of FORD MOTOR COMPANY	Ground
C4337-3	Courtesy of FORD MOTOR COMPANY	Ground

Positive Lead	Measurement / Action	Negative Lead
C4338-1	Courtesy of FORD MOTOR COMPANY	Ground
C4338-3	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes	GO to M4.
No	REPAIR the circuit in question.

M4 CHECK THE AUDIO CIRCUITS TO THE SUSPECT D-PILLAR SPEAKER FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4337-1	Courtesy of FORD MOTOR COMPANY	C4326B-5
C4337-3	Courtesy of FORD MOTOR COMPANY	C4326B-13

Positive Lead	Measurement / Action	Negative Lead
C4338-1	Courtesy of FORD MOTOR COMPANY	C4326B-5
C4338-3	Courtesy of FORD MOTOR COMPANY	C4326B-13

Are the resistances less than 3 ohms?

Yes	GO to M5.
No	REPAIR the circuit in question.

M5 CHECK THE AUDIO CIRCUITS TO THE SUSPECT D-PILLAR SPEAKER FOR A SHORT TOGETHER

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4337-1	Courtesy of FORD MOTOR COMPANY	C4337-3

Positive Lead	Measurement / Action	Negative Lead
C4338-1	Courtesy of FORD MOTOR COMPANY	C4338-3

Is the resistance greater than 10, 000 ohms?

Yes	GO to M6.
No	REPAIR the circuits.

M6 CHECK FOR CORRECT DSP MODULE OPERATION

Ignition OFF.

Disconnect and inspect the DSP module connectors and related in-line connectors.

Repair:
- Corrosion (clean module pins or install new connectors or terminals)
- Damaged or bent pins (install new terminals or pins)
- Pushed-out pins (install new pins as necessary)

Reconnect the DSP module connectors 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 TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new DSP module. 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.