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Check the Leads Between the Microphone and the Main Unit




Check The Leads Between The Microphone And The Main Unit







Unplug the connector:
- Mobile telephone connection (375)

Unplug the connector:
- Microphone, roof console (634)






















Take a resistance reading between
- 3 - Microphone, roof console
- 3 - Mobile telephone connection

The reading should be 0 Ohm - 1 Ohm

Checking the wiring harness
Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.

Is the function correct?

NO - Rectifying the Lead - I

YES - Continue With Check The Leads Between The Microphone And The Main Unit






















Take a resistance reading between
- 2 - Microphone, roof console
- 10 - Mobile telephone connection

The reading should be 0 Ohm - 1 Ohm

Checking the wiring harness
Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.

Is the function correct?

NO - Rectifying the Lead - II

YES - Continue With Check The Leads Between The Microphone And The Main Unit






















Take a resistance reading between
- 1 - Microphone, roof console
- 9 - Mobile telephone connection

The reading should be 0 Ohm - 1 Ohm

Checking the wiring harness
Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.

Is the function correct?

NO - Rectifying the Lead - III

YES - Continue With Check The Leads Between The Microphone And The Main Unit

















Measure the resistance. The value should be Infinite.
- 3 - Microphone, roof console
- - Good grounding point

Checking the wiring harness
Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.

Is the function correct?

NO - Rectifying the Lead - I

YES - Continue With Check The Leads Between The Microphone And The Main Unit

















Measure the resistance. The value should be Infinite.
- 2 - Microphone, roof console
- - Good grounding point

Checking the wiring harness
Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.

Is the function correct?

NO - Rectifying the Lead - II

YES - Continue With Check The Leads Between The Microphone And The Main Unit

















Measure the resistance. The value should be Infinite.
- 1 - Microphone, roof console
- - Good grounding point

Checking the wiring harness
Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.

Is the function correct?

NO - Rectifying the Lead - III

YES - Checking the Handsfree Unit