GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B1283: Television Antenna 1 Performance

DTC B1284: Television Antenna 2 Performance

DTC B1285: Television Antenna 3 Performance

DTC B1286: Television Antenna 4 Performance

Circuit/System Description

The TV antenna signal circuits consists of 4 individual coaxial cables that carries the TV signal information received by the TV antenna through the TV antenna amplifier and then to the TV antenna module.

Conditions for Running the DTC

This test is run every 300 milliseconds.

Conditions for Setting the DTC

The TV antenna module detects a open or short to ground on one or more of the 4 TV antenna coax cables for 20 seconds.

Action Taken When the DTC Sets

The TV antenna module disables all 4 coax cables when a short to ground is detected in one or more of the TV antenna inputs. When the TV antenna detects an open in one or more TV antenna coax inputs the remainder of the 4 unaffected TV antenna coax inputs continue to operate.

Conditions for Clearing the DTC

    • The condition must be corrected.
    • The DTC clears after the TV function has been cycled between OFF and ON.

Reference Information

Schematic Reference

Radio/Navigation System Schematics

Connector End View Reference

Entertainment/Communication Connector End Views

Description and Operation

Radio/Audio System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Testing

  1. With the TV function OFF, disconnect the 4 TV coaxial cables at the TV antenna amplifier.
  2. With the TV function ON wait 20 seconds, test for greater than 1 volt at each of the 4 TV coax cable center conductors.
  3. If 1TV coaxial cable center connector is less than 1 volt, replace the suspect TV antenna coaxial cable.
    If all 4 TV coaxial cable center connectors are less than 1 volt, see Component Testing (Coaxial Cables - TV Antenna Module to TV Antenna Amplifier).
  4. With the TV function OFF, reconnect the 4 TV coaxial cables to the TV antenna amplifier.
  5. Disconnect the 4 TV coaxial cables at the TV antenna.
  6. With the TV function ON wait 20 seconds, test for greater than 1 volt at each of the 4 TV coax cable center conductors.
  7. If all 4 TV coaxial cable center connectors are less than 1 volt, see Component Testing (Coaxial Cables - TV Antenna Amplifier to TV Antenna).
  8. If all 4 TV coaxial cable center connectors are greater than 1 volt replace the rear glass (TV antenna).
  9. If 1TV coaxial cable center connector is less than 1 volt, replace the suspect TV antenna coaxial cable.

Component Testing (Coaxial Cables - TV Antenna Module to TV Antenna Amplifier)

Important: Perform the Circuit/System Testing before using this diagnostic.

  1. Ignition Off. Disconnect the 4 TV coaxial cables from the TV antenna module and the TV antenna amplifier. Test for less than 5 ohms resistance on each TV antenna coaxial cable center conductor from end to end.
  2. If the resistance is greater than 5 ohms, replace the suspect TV antenna coaxial cable.
  3. Test for less than 5 ohms resistance on all 4 TV antenna coaxial cables outer shields from end to end.
  4. If the resistance is greater than 5 ohms , replace the suspect TV antenna coaxial cable.
  5. Test for infinite resistance on all 4 TV antenna coaxial cables between the center conductor and the outer conductor.
  6. If there is less than infinite resistance, replace the suspect TV antenna coaxial cable.
    If all coaxial cable tests normal, replace the TV antenna module.

Component Testing (Coaxial Cables - TV Antenna Amplifier to TV Antenna)

Important: Perform the Circuit/System Testing before using this diagnostic.

  1. Ignition Off. Disconnect the 4 TV coaxial cables from the TV antenna amplifier and the TV antenna.
  2. Test for less than 5 ohms resistance on each TV antenna coaxial cable center conductor from end to end.
  3. If the resistance is greater than 5 ohms, replace the suspect TV antenna coaxial cable.
  4. Test for less than 5 ohms resistance on all 4 TV antenna coaxial cables outer shields from end to end.
  5. If the resistance is greater than 5  ohms , replace the suspect TV antenna coaxial cable.
  6. Test the resistance of all 4 TV antenna coaxial cables between the center conductor and the outer conductor. Verify there is infinite resistance between both conductors.
  7. If there is less than infinite resistance, replace the suspect TV antenna coaxial cable.
  8. If the coaxial cable tests normal, replace the TV antenna amplifier.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Television Antenna Amplifier Replacement
    •  Television Antenna Module Replacement