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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Avalanche - 2WD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Trailer Brake Control Relay Replacement

Trailer Brake Control Relay Replacement 1500

Removal Procedure
  1. Turn the ignition switch to the OFF position.

    2. Note: Do not remove the spare wheel hoist.

  2. Remove the spare tire and wheel assembly. Refer to Spare Wheel Hoist Replacement.

    3. Object Number: 2127555 Size: SH
  3. Disconnect the trailer brake control relay electrical connector.

    4. Note: It is not necessary to completely remove the bolts.

  4. Loosen, but do not remove, the trailer brake control relay bolts (1).

    5. Object Number: 2127559 Size: SH
  5. Slide the trailer brake control relay (1) toward the center of the vehicle and remove the trailer brake control relay.

Installation Procedure

    Object Number: 2127559 Size: SH
  1. If installing a new trailer brake control relay, hand start the 2 trailer brake control relay bolts.
  2. Position the trailer brake control relay to the frame bracket.
  3. Slide the trailer brake control relay (1) toward the left frame rail.

    4. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 2127555 Size: SH
  4. Tighten the trailer brake control relay bolts (1) to  6 N·m (53 lb in).
  5. Connect the trailer brake control relay electrical connector.
  6. Install the spare tire and wheel assembly. Refer to Spare Wheel Hoist Replacement.

Trailer Brake Control Relay Replacement 2500

Removal Procedure
  1. Turn the ignition switch to the OFF position.

    2. Note: Do not remove the spare wheel hoist.

  2. Remove the spare tire and wheel assembly. Refer to Spare Wheel Hoist Replacement.

    3. Object Number: 2154132 Size: SH
  3. Disconnect the trailer brake control relay electrical connector.

    4. Note: It is not necessary to completely remove the bolts.

  4. Loosen, but do not remove, the trailer brake control relay bolts (1).

    5. Object Number: 2154137 Size: SH
  5. Slide the trailer brake control relay (1) toward the rear of the vehicle and remove the trailer brake control relay.

Installation Procedure

    Object Number: 2154137 Size: SH
  1. If installing a new trailer brake control relay, hand start the 2 trailer brake control relay bolts.
  2. Position the trailer brake control relay to the frame rail.
  3. Slide the trailer brake control relay (1) forward on the frame rail.

    4. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 2154132 Size: SH
  4. Tighten the trailer brake control relay bolts (1) to  6 N·m (53 lb in).
  5. Connect the trailer brake control relay electrical connector.
  6. Install the spare tire and wheel assembly. Refer to Spare Wheel Hoist Replacement.