Pinpoint Test B: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - Vehicles Without Navigation
Information and Entertainment System
Pinpoint Tests
Pinpoint Test B: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - Vehicles Without Navigation
Refer to Wiring Diagram Set 130 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), Audio System/Navigation for schematic and connector information. Diagrams By Number
Normal Operation
The Audio Control Module (ACM) directs audio signals to the speakers in the form of an AC voltage. The ACM provides internal circuit protection for shorts to ground or shorts to voltage. The tweeter speakers are integral to the front door speakers, and cannot be replaced separately.
A short to ground or short to voltage in the circuitry to one of the speakers can cause multiple speakers to lose sound due to the built-in overload protection feature of the ACM. In this case, a speaker fault DTC sets, and this pinpoint test should be followed to isolate the damaged circuit.
It should also be noted that when the ACM activates the built-in overload protection, DTC B1342 can also set. The circuit failure must be repaired before DTC B1342 can be cleared.
- DTC B2965 (Audio System Speaker Circuit Fault) - sets when an open, short to ground, or short to voltage is detected on any of the speaker circuits.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Speaker
- ACM
PINPOINT TEST B: POOR QUALITY/DISTORTED/NO SOUND FROM ONE OR MORE SPEAKERS (NOT ALL SPEAKERS) - VEHICLES WITHOUT NAVIGATION
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
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B1 CHECK THE AUDIO SIGNALS TO THE SUSPECT SPEAKER
- Ignition OFF.
- Disconnect: Suspect Speaker.
- Operate the audio system in radio tuner (AM/FM) mode.
- Measure the AC voltage between the suspect speaker pin 1 and pin 2, harness side as follows:
- Is a fluctuating AC voltage present?
Yes
INSTALL a new speaker for the suspect speaker. REFER to Door Speaker Door Speaker. CLEAR any DTCs present. REPEAT the self-test.
No
GO to B2 .
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B2 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: ACM C240a.
- Ignition ON.
- Measure the voltage between the suspect speaker, harness side and ground as follows:
- Is any voltage present?
Yes
REPAIR the circuit in question. CLEAR any DTCs present. REPEAT the self-test.
No
GO to B3.
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B3 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between the suspect speaker, harness side and ground as follows:
- Are the resistances greater than 10,000 ohms?
Yes
GO to B4.
No
REPAIR the circuit in question. CLEAR any DTCs present. REPEAT the self-test.
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B4 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER FOR AN OPEN
- Measure the resistance between the ACM, harness side and the suspect speaker, harness side as follows:
- Are the resistances less than 5 ohms?
Yes
GO to B5.
No
REPAIR the circuit in question. CLEAR any DTCs present. REPEAT the self-test.
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B5 CHECK FOR CORRECT ACM OPERATION
- Connect: All Disconnected Connectors.
- Disconnect all the ACM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the ACM connectors and make sure they seat correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
Yes
INSTALL a new ACM. REFER to Audio Control Module (ACM) Audio Control Module (ACM). TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR any DTCs present. REPEAT the self-test.
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