Checking Carphone Antenna

Checking the carphone antenna

Checking the component

Hint: If there is an extra antenna available, use it for a comparative test by connecting it to the phone module (PHM) or the A-post connector.

Note! The antenna must be pointing forward, immediately under the existing antenna.

Checking the connectors and cables
Disconnect the connector at the phone module (PHM) and take readings at the connector in the A-post between:
- screen and ground
- signal and ground
- screen and signal.
The resistance must be infinite. Replace the cable if the resistance is not infinite.
Measure the voltage from the connector in the A-post between screen and ground. The voltage must be 0 V. Replace the antenna cable if the voltage is not 0 V.
Check that the cable terminals in the connector at the phone module (PHM) and in the A-post are securely crimped. Remedy or replace if damaged.

Other information:
- Antenna carphone, replacing Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals





Was a fault detected?

Yes - Verification

No - Checking the connectors and wiring

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Verification




Verification

Symptom verification

Hint: After carrying out the repair check that the fault has been remedied.








- Ignition off.
- Reinstall the connectors, components etc.
- Ignition on.
Check the telephone antenna by using the telephone, see user's manual.

Does the telephone antenna work?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFICATION FAILED - Fault-tracing information

VERIFIED - FAULT FOUND

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Fault-tracing information

Attempt New Test - Checking the component

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Checking the connectors and wiring
Raise the secondary lock on the connector in the right A-pillar.
Loosen the primary lock and remove the insulator.
Carefully remove the antenna from the headlining.
Measure the resistance between the signal line and screen ground on the connector. The resistance must be approximately 0 ohms.
Measure the resistance between screen ground and ground. The resistance must be infinite.
Carefully remove the three screws that hold the antenna's circuit board.
Carefully lift up the circuit board from the mounting point so that there is no contact between the circuit board and the casing.
Measure the resistance between the signal line and screen ground. The resistance must be infinite. If the resistance is infinite there is a short-circuit between the signal line and screen ground.
Remedy as necessary.
Erase any diagnostic trouble codes (DTCs) after fault-tracing.
Perform a function check.
If the check succeeds, the malfunction has been fixed.

Other information
- Carphone antenna, replacing Service and Repair
- Connectors, repair Connectors, Repair
- Checking wiring and terminals Checking Wiring and Terminals





Was a fault detected?

Yes - Verification

No - Fault-tracing information

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