For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: This table is used to diagnose audio distortion on one or more speakers on a Base or BOSE® audio system.
1 | Did you perform the Radio/Audio System Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Radio/Audio System
2 |

1. Turn ON the ignition, with the engine OFF.
2. Turn ON the radio.
3. Insert the tape or CD from the J39916-A Speaker Diagnostic Kit.

Can audio distortion be heard from any speakers?

--

Go to Step 3

Go to Audio System Troubleshooting Hints

3 | Can audio distortion be heard from all speakers? | -- | Go to Step 4 | Go to Step 5
4 | Is the vehicle equipped with a remote amplifier? | -- | Go to Step 6 | Go to Audio System Troubleshooting Hints
5 | Test the appropriate speaker outputs from the radio or remote amplifier (if equipped) for a short to ground or an open. Refer to Testing for Short to Ground and Testing for Continuity in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 7
6 | Does the audio system (with a remote amp) have a pop noise when the radio is turned ON or OFF? | -- | Go to Step 8 | Go to Audio System Troubleshooting Hints
7 | Inspect for poor connections at the harness connector of the speaker. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 9
8 |

1. Turn OFF the radio.
2. Make sure the ignition is turned OFF.
3. Measure the voltage on the amp enable circuit. (At sound processor connector C1 terminal D2 or amp connector terminal 25.)

Is any voltage measured on the amp enable circuit?

--

Go to Step 11

Go to Step 12

9 | Replace the speaker. Did you complete the replacement? | -- | Go to Step 10 | --
10 | Operate the system for which the symptom occurred. Is the symptom still present? | -- | Go to Step 2 | System OK
11 |

1. Replace the sound processor.
2. Note: Before replacing the sound processor, test the amp enable circuit for an intermittent short to ground. Refer to Testing for Electrical Intermittents in Wiring Systems. Repair as needed.

Is the replacement complete?

--

Go to Step 10

--

12 |

1. Substitute the amplifier with a known good unit.
2. Operate the system for which the symptom occurred.

Is the symptom still present?

--

Go to Step 13

Go to Step 14

13 |

1. Replace the radio and perform the set up procedure.
2. Install a scan tool.
3. Select RADIO THEFT from the SPECIAL FUNCTIONS menu.
4. Follow the instructions on the screen.

Did you complete the replacement?

--

Go to Step 10

--

14 | Replace the test amplifier with a new unit. Is the replacement complete? | -- | Go to Step 10 | --