For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Does the reduced reception or lack of reception occur with more than one radio station? | -- | Go to Step 3 | Go to Step 2
2 | Complete the following steps in order to test the vehicle electrical system for the cause of interference at a particular frequency:

1. Turn the ignition switch to the ON position.
2. Tune the radio to the affected station.
3. Remove one fuse at a time until the faulty circuit is identified.
4. Make the necessary repair to the faulty circuit.

Has the repair been made?

--

Go to Radio/Audio System Check

--

3 |

1. Disconnect the negative battery cable.
2. Disconnect the antenna lead-in connector at the radio receiver.
3. Use a J 39200 in order to measure the resistance between the antenna lead-in connector ground to the battery ground cable.

Is the resistance greater than the specified value?

0.15ohms

Go to Step 4

Go to Step 5

4 |

1. Disconnect the antenna lead-in connector at the windshield.
2. Use a J 39200 in order to measure the resistance between the coaxial shield ground (G390) and the radio connector shielded circuit.

Is the resistance greater than the specified value?

0.2ohms

Go to Step 8

Go to Step 10

5 | Use a J 39200 in order to measure the resistance at the center conductor (signal feed) between the antenna connector and the radio connector. Is the resistance greater than the specified value? | 2ohms | Go to Step 7 | Go to Step 6
6 | Use a J 39200 in order to measure the resistance at the center conductor (signal feed) and the coaxial ground (shielding). Is the resistance less than the specified value? | OL (infinite) | Go to Step 9 | Go to Step 11
7 |

1. Inspect the coaxial cable and the inter-connects for a faulty connection or corrosion.
2. Repair the cable and the inter-connects as needed.
3. If the cable and the inter-connects are OK, replace the antenna coaxial cable.

Has the repair been made?

--

Go to Radio/Audio System Check

--

8 |

1. Inspect the coaxial cable ground at C290 for a faulty or corroded connection.
2. Repair the ground as needed.
3. If the ground is OK, replace the coaxial cable.

Has the repair been made?

--

Go to Radio/Audio System Check

--

9 | Replace the affected section of the coaxial cable. Has the repair been made? | -- | Go to Radio/Audio System Check | --
10 | Repair the faulty connection or corrosion at G390 (coaxial ground cable). Has the repair been made? | -- | Go to Radio/Audio System Check | --
11 |

1. Inspect the coaxial connector at the windshield for a faulty connection or corrosion.
2. Replace the radio with a known good radio.
3. If the reception is not improved, replace the windshield.

Has the repair been made?

--

Go to Radio/Audio System Check

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