For 1990-2009 cars

Step | Action | Value | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Radio/Audio System Schematics Connector End View Reference: Entertainment Connector End Views
1 | Did you review the Description and Operation and perform the necessary inspections? | -- | Go to Step 2 | Go to Radio/Audio System Description and Operation
2 |

1. Turn the radio ON.
2. Adjust the volume to the lowest level that can be heard.

Is the lowest audible setting too loud?

--

Go to Step 3

Go to Audio System Troubleshooting Hints

3 | Compare the volume to a similar vehicle equipped with the same audio system. Are both vehicles the same? | -- | System OK | Go to Step 4
4 | Use the On Beard Diagnostics to check the radio EQ setting. Does the EQ setting match the specified value? | EQ:00 | Go to Step 9 | Go to Step 5
5 |

1. Disconnect the amplifier.
2. Turn the radio ON.
3. Using DVOM, measure the voltage at the amplifier present circuit at the amplifier.

Is the voltage reading equivalent to the specified value?

12 V

Go to Step 8

Go to Step 6

6 | Inspect the radio for poor or loose connections. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 7
7 | Test for an open, high resistance, or short to ground in the amplifier present circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 9
8 |

1. Disconnect the amplifier 24-way connector.
2. Use a fused jumper wire to jump the amplifier present circuit to ground.
3. Recheck the EQ setting?

Does the EQ setting match the specified value?

EQ:00

Go to Step 10

Go to Step 9

9 | Replace the radio. Refer to Radio Replacement . Did you complete the repair? | -- | Go to Step 11 | --
10 | Replace the amplifier. Refer to Radio Speaker Amplifier Replacement . Did you complete the repair? | -- | Go to Step 11 | --
11 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2