Cellular Telephone Microphone Malfunction

/ 9-5 (9650) / 2011 / 3. Electrical System / Audio system with navigation / Fault diagnosis, fault symptoms / Cellular Telephone Microphone Malfunction

Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

Without Navigation Radio

The mobile telephone control module uses the cellular telephone microphone to allow driver communication with cellular telephone.

With Navigation Radio

The mobile telephone control module and navigation radio use the cellular telephone microphone to allow driver communication with a cellular telephone, as well as to operate the voice recognition guidance feature of the navigation radio.

Reference Information

Schematic Reference

Cellular Telephone Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Cellular Telephone Description and Operation

Electrical Information Reference

•	Circuit Testing

•	Connector Repairs

•	Testing for Intermittent Conditions and Poor Connections

•	Wiring Repairs

Circuit/System Testing

Without Navigation Radio

1.	Ignition OFF, disconnect the harness connector at the B24 cellular phone microphone.

2.	Ignition OFF, test for less than 5 Ω between the low reference circuit terminal 2 and ground.

3.	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K82 mobile telephone control module.

4.	Ignition ON, test for 9-11 V between the signal circuit terminal 3 and ground.

5.	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K82 mobile telephone control module.

6.	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K82 mobile telephone control module.

7.	If all circuits test normal, replace the B24 cellular phone microphone.

With Navigation Radio

1.	Ignition OFF, disconnect the X1 harness connector at the A11 Radio and the harness connector at the B24 Cellular Phone Microphone.

2.	Ignition OFF, test for infinite resistance between the low reference circuit terminal 2 and ground.

3.	If less than the specified range, test the low reference circuit for an short to ground or an high resistance.

4.	Ignition ON, test for less than 0.3 V between the signal circuit terminal 3 and ground.

5.	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal.

6.	Ignition OFF, reconnect the X1 harness connector at the A11 Radio.

7.	Ignition ON, test for 9-11 V between the signal circuit terminal 3 and ground.

8.	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K82 mobile telephone control module.

9.	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K82 mobile telephone control module.

10.	If all circuits test normal, replace the B24 cellular phone microphone.

11.	If condition still exists, replace the A11 Radio.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Mobile Telephone Microphone Replacement

•	Control Module References for control module replacement, setup and programming.

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