Pinpoint Test Q: Poor Reception
Ford Work Solutions(TM)
Pinpoint Tests
Pinpoint Test Q: Poor Reception
Refer to Wiring Diagram Set 141, Ford Work Solutions for schematic and connector information. Diagrams By Number
Normal Operation
The AM/FM antenna receives AM and FM radio waves and sends them to the Audio Control Module (ACM).
The enable circuit for the AM/FM antenna is hard-wired to the ACC power circuit, as the in-dash computer cannot power the antenna.
The noise suppression equipment reduces engine ignition and electrical systems interference transmitted through the speakers.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- AM/FM antenna
- AM/FM antenna cable
- Charging system
- Ignition system
- Noise suppression equipment
PINPOINT TEST Q: POOR RECEPTION
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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Q1 CHECK THE AUDIO SYSTEM RECEPTION
- Operate the audio system in radio tuner (AM/FM) mode.
- Check the reception with the engine running, and with the engine off.
- Does the poor reception only occur with the engine running?
Yes
GO to Q2.
No
GO to Q6.
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Q2 CHECK THE NOISE SUPPRESSION EQUIPMENT
- Check all required noise suppression equipment and the radio frequency suppression bond for security, cleanliness, and metal-to-metal contact.
- Are the connections clean, secure, and in metal-to-metal contact?
Yes
GO to Q3.
No
CLEAN and SECURE the connections, or INSTALL new noise suppression equipment as needed. TEST the system for normal operation.
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Q3 CHECK THE RADIO INTERFERENCE CAPACITOR
- Install a new radio interference capacitor.
- Start the engine.
- Operate the audio system in radio tuner (AM/FM) mode.
- Is the reception OK?
Yes
The cause of the concern was an inoperative radio interference capacitor. The system is now operating correctly.
No
GO to Q4.
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Q4 CHECK THE GENERATOR
- Ignition OFF.
- Disconnect: Generator C102a .
- Start the engine.
- Operate the audio system in radio tuner (AM/FM) mode.
- Is the reception OK?
Yes
INSTALL a new generator. REFER to Charging System Service and Repair. TEST the system for normal operation.
No
GO to Q5.
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Q5 CHECK THE IGNITION CIRCUITS
- Ignition OFF.
- Connect: Generator C102a .
- Check the ignition circuits for correct routing, grounding, and integrity of the connections.
- Operate the audio system in radio tuner (AM/FM) mode.
- Is the reception OK?
Yes
INSTALL a new generator. REFER to Charging System Service and Repair. TEST the system for normal operation.
No
GO to Q6.
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Q6 CHECK THE AM/FM ANTENNA ENABLE CIRCUIT
- Ignition OFF.
- Disconnect: AM/FM Antenna C2086 .
- Ignition ON.
- Measure the voltage between the AM/FM antenna C2086-1, circuit 15S-MD7 (GN/BU), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to Q7.
No
REPAIR the circuit. TEST the system for normal operation.
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Q7 CHECK THE AM/FM ANTENNA CABLE
- Ignition OFF.
- Disconnect: AM/FM Antenna Cable at AM/FM Antenna .
- Disconnect: AM/FM Antenna Cable at In-Dash Computer .
- Measure the resistance of the AM/FM antenna cable core between the AM/FM antenna and the in-dash computer; and measure the resistance of the AM/FM antenna cable between the core and shield.
- Is the resistance less than 2 ohms between the AM/FM antenna and the in-dash computer, and greater than 10,000 ohms between the AM/FM antenna cable core and shield?
Yes
GO to Q8.
No
INSTALL a new AM/FM antenna cable. REFER to Antenna Cable - AM/FM Service and Repair. TEST the system for normal operation.
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Q8 ISOLATE THE AM/FM ANTENNA
- Connect: AM/FM Antenna Cable at In-Dash Computer .
- Install a new AM/FM antenna. Refer to Antenna - AM/FM Antenna - AM/FM.
- Operate the audio system in radio tuner (AM/FM) mode.
- Is the reception OK?
Yes
The concern was caused by an inoperative AM/FM antenna. The system is now operating correctly.
No
INSTALL a new AM/FM antenna cable. Refer to Antenna Cable - AM/FM Service and Repair. TEST the system for normal operation.
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