For 1990-2009 cars
Handling ESD Sensitive Parts Notice
Entertainment Connector End Views
Ground Distribution Schematics
Entertainment Components
Radio/Audio System Schematics

### Circuit Description

The Video Entertainment System (VES) controls the operation of the rear speakers. The Auxiliary Video Module (AVM) has an audio amplifier which is used to sound video audio through the rear speakers. The Interface Module (IM) senses when the radio is in use through CKT 145. When the radio is off, the IM allows the rear speakers to sound video audio. However, when the radio is turned on, the IM mutes the rear speakers; video audio is then available through the headphone jacks at the second or third seat audio controls only. This action prevents two sources of audio to be heard at the same time (radio audio through the front speakers and video audio through the rear speakers.)

### Diagnostic Aids

• | Check for the following conditions:

- | An open in CKT 145 between the radio and the AVM

- | An open in CKT 145 between the AVM and the IM

- | An open in CKT 150 between the IM and the AVM

- | A faulty radio

- | A faulty IM

• | An intermittent failure may be very difficult to detect and to diagnose accurately. Faulty electrical connections or wiring causes most intermittent problems. When an intermittent condition is suspected, check the suspected circuits for the following conditions:

- | Poor mating of connector halves or backed out terminals

- | Improperly formed or damaged terminals

- | Wire chafing

- | Poor wire to terminal connections

- | Dirty or corroded terminals

- | Damage to connector bodies

- | Wire broken inside the insulation

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. Determines whether the malfunction is at the radio, or at the AVM or IM.

2. Determines whether the IM or AVM is faulty.

3. for an open in CKT 150.

4. Tests if CKT 145 is open between the radio and the AVM, or that the radio is not sending voltage signal when radio is on.

5. Verifies repairs made to the VES.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: The rear speakers do not mute when the radio is turned on, causing the rear speakers to play video audio while the radio is on.
1 |

1. Turn the ignition switch on.
2. Turn on the radio.
3. Using a J 39200 digital multimeter (DMM), measure the voltage by backprobing between the Auxiliary Video Module (AVM) harness connector C1 terminal B and ground.

Does the voltage measure in the specified range?

B+ (10-14 V)

Go to Step 2

Go to Step 5

2 | Using a J 39200 DMM, measure the voltage by backprobing between the AVM harness connector C3 terminal D and ground. Does the voltage measure in the specified range? | B+ (10-14 V) | Go to Step 3 | Go to Step 4
3 | Using a J 39200 DMM, measure the voltage by backprobing between the AVM harness connector C3 terminal B and B+. Does the voltage measure in the specified range? | B+ (10-14 V) | Go to Step 8 | Go to Step 9
4 |

1. Test for a poor connection or an open in CKT 145 between the AVM harness connector C3 terminal D and the Auxiliary Video Module (AVM).
2. If CKT 145 is OK, then replace the AVM.

Refer to Audio/Video Interface Module Replacement .

Is the repair complete?

--

Go to Step 10

--

5 | Using a J 39200 DMM, measure the voltage by backprobing between the radio harness connector C1 terminal 8 and ground. (Note: radio connector still connected to the radio with radio turned on.) Does the voltage measure in the specified range? | B+ (10-14V ) | Go to Step 6 | Go to Step 7
6 | Repair the poor connection or the open in CKT 145 between the radio harness connector C1 terminal 8 and the Auxiliary Video Module (AVM). Is the repair complete? | -- | Go to Step 10 | --
7 |

1. Test the radio connector C1 terminal 8 for a poor connection.
2. If the connection is OK, then replace the radio. Refer to Radio Replacement .

Is the repair complete?

--

Go to Step 10

--

8 |

1. Test for poor connections at the Interface Module (IM).
2. If the connections are OK, then replace the IM. Refer to Interface Module Replacement .

Is the repair complete?

--

Go to Step 10

--

9 |

1. Test for a poor connection or an open in CKT 150 between the IM and the AVM.
2. If the connection is OK, then replace the AVM. Refer to Audio/Video Interface Module Replacement .

Is the repair complete?

--

Go to Step 10

--

10 |

1. Turn the ignition switch off.
2. Reconnect the connectors or components that were previously removed.
3. Verify that the Video Entertainment System (VES) operates properly.

Does the VES operate normally?

--

System OK

Go to Video System System Check