Removal Procedure

IMPORTANT: It is essential to comply with the instructions for the hydraulic modulator and the ABS control unit. Refer to ABS Control Unit General Repair Specification .

Remove the cover of the brake fluid reservoir.
Siphon out as much brake fluid as possible with a siphon bottle.
Remove the battery.
- Remove the ground connection from the ground terminal.
  Release the nut.
- Remove the positive connection from the battery.
  Remove the nut.
- If present, remove the thermal protection.
- Remove the bracket.
  Remove the bolt.
- Remove the battery.

Fig 1: View Of Preheater System Control Unit, Wiring Harness Plug, Clip, Cable Ties And Bolts

Courtesy of GENERAL MOTORS CORP.

Remove the battery support.
- For diesel engines, remove the preheater system control unit (4).
- Remove the wiring harness plug (3).
- Remove the coolant hose.
- Release the clip (5).
- Remove the wiring harness.
  Disconnect the 2 cable ties (1).
- Remove the 3 bolts (2).
- Remove the hydraulic modulator.

IMPORTANT: Cooling system remains sealed.

Remove the coolant surge tank.
Disconnect the wiring harness plug.

Set the coolant surge tank aside.

Fig 2: View Of Hydraulic Modulator Hydraulic Lines And Bolts

Courtesy of GENERAL MOTORS CORP.

Remove the hydraulic modulator.
- Disconnect the hydraulic modulator wiring harness plug.
- Remove the 6 hydraulic lines (2).
- Install the 6 sealing plugs on the hydraulic modulator.
- Remove the 3 bolts (1).