GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

  1. Disconnect the negative battery cable.
  2. Disconnect the antenna lead-in harness connector at the radio receiver.
  3. Using a DMM, measure the resistance between the antenna lead-in harness connector and ground.

Is the resistance measured greater than specified?

0.15 ohms

Go to Step 8

Go to Step 2

2

  1. Leave the DMM connected.
  2. Wiggle the antenna lead-in harness connector at the radio antenna module.

Does the DMM indicate intermittent continuity?

--

Go to Step 8

Go to Step 3

3

Is the coax cable type RG-58 or RG-59?

--

Go to Step 4

Go to Step 5

4

Is the measured resistance less than 0.2ohms?

--

Go to Step 6

Go to Step 10

5

For RG-62 or RG-62M, does the measured resistance approximately equal the value?

Less than 3.5ohms

Go to Step 6

Go to Step 10

6

While observing the DMM, wiggle the antenna coax.

Does the meter indicate intermittent continuity?

--

Go to Step 10

Go to Step 7

7

  1. Disconnect the radio antenna module harness connector.
  2. Turn the ignition switch on.
  3. Turn the radio on.
  4. Using a DMM, measure the voltage between the radio antenna module harness connector terminal A and terminal B.

Is the voltage measured within the specified value?

10-14V

Go to Step 10

Go to Step 9

8

Check the radio antenna module and the coaxial cable interconnects for a poor connection or corrosion.

Are all connections clean, tight and free of corrosion?

--

Go to Step 11

Go to Step 10

9

Using a DMM, measure the voltage between the radio antenna module harness connector terminal A and ground.

Is the voltage measured within the specified range?

10-14V

Go to Step 12

Go to Step 13

10

  1. Check the coaxial cable interconnects for a poor connection or corrosion.
  2. Repair or replace the antenna coaxial circuit as necessary. Refer to Radio Antenna Cable Extension Cable Replacement or Radio Antenna Cable Extension Cable Replacement for service procedure.

Is the repair complete?

--

Go to Diagnostic System Check - Radio/Audio System

--

11

Replace the radio antenna module. Refer to Radio Speaker Amplifier Replacement for service procedure.

Is the repair complete?

--

Go to Diagnostic System Check - Radio/Audio System

--

12

Repair poor connection or open in circuit 351.

Is the repair complete?

--

Go to Diagnostic System Check - Radio/Audio System

--

13

Repair poor connection or open in circuit 145.

Is the repair complete?

--

Go to Diagnostic System Check - Radio/Audio System

--