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Replacement Of Ecu For Abs Repair (06-31-03R)

Publication date: 2004-12-08
Reference number: 06-31-03R

REPLACEMENT OF ECU FOR ABS REPAIR

REPLACEMENT OF ECU FOR ABS REPAIR

TECHNICAL SERVICE BULLETIN

Reference Number(s): 06-31-03R, Date of Issue:  December 8, 2004
SUBARU: 1997-2004MY Legacy, Outback & Baja (Excluding VDC Equipped Vehicles); 1998-2004MY Impreza and Forester
Superceded Bulletin(s): 06-31-03, Date of Issue:  December 8, 2004

INTRODUCTION

In order to improve serviceability of ABS system, the ECU was subdivided and has been newly established as a spare part. This service bulletin details the part numbers and replacement procedures of the ECU as a spare part.

PARTS NUMBERS AND APPLICABLE MODELS

PARTS NUMBERS AND APPLICABLE VEHICLE

VEHICLE MODEL YEAR TRANS TYPE ECU SPARE PART IDENTIFICATION MARK HYDRAULIC CONTROL UNIT / ECU ASSY
Legacy(1) 97 & 98 AT 27529AC03A C3 27539AC03A
Legacy(1) 97 & 98 MT 27529AC04A C4 27539AC04A
Legacy(1) 99 to 01 AT 27529AC05A C5 27539AC05A
Legacy(1) 99 to 01 MT 27529AC06A C6 27539AC06A
Legacy(1) 02 to 04 AT 27529AE04B CG 27539AE04B
Legacy(1) 02 to 04 MT 27529AE05B CH 27539AE05B
Outback(2) 00 & 01 AT 27529AE02A CE 27539AE02A
Outback(2) 00 & 01 MT 27529AE03A CF 27539AE03A
Outback(2) 02 to 04 AT 27529AE06B CI 27539AE06B
Outback(2) 02 to 04 MT 27529AE07B CJ 27539AE07B
Impreza 98 to 01 AT 27529AC050 C5 27539AC050
Impreza 98 to 01 MT 27529AC060 C6 27539AC060
Impreza 02 & 03 AT 27529FE110 CC 27539FE110
Impreza 02 & 03 MT 27529FE120 CD 27539FE120
Impreza 04 AT 27529FE170 CU 27539FE170
Impreza 04 MT 27529FE180 CV 27539FE180
Impreza 04 MT
with DCCD		 27529FE200 CY 27539FE200
Forester 98 AT 27529AC030 C3 27539AC030
Forester 98 MT 27529AC040 C4 27539AC040
Forester 99 to 02 AT 27529FC000 C7 27539FC000
Forester 99 to 02 MT 27529FC010 C8 27539FC010
Forester 03 & 04 AT 27529SA001 CO 27594SA000
Forester 03 & 04 MT 27529SA011 CP 27594SA010
(1) Legacy includes Outback models from 97MY to 99MY.
(2) Outback models includes Baja.

REPAIR PROCEDURE

  1. Turn off the ignition switch.
  2. Disconnect the negative terminal from the battery.
  3. Disconnect the air intake duct from the Air Box.
  4. Remove the air cleaner case from the inner fender well.

Removal of ECU

NOTE: When removing the ECU, the brake pipes remain connected.
  1. Disconnect all electrical connections from the ECU (top and bottom).
  2. Remove the two installation bolts (M8) from the bracket of the hydraulic unit and the ECU assembly.
    Fig 1: Locating ECU Connector And Bracket Installation Unit
    G02605626Courtesy of SUBARU OF AMERICA, INC.
  3. Lift the hydraulic unit and the ECU assembly from the bracket by about 5 cm (0.2 inches) and support it with a small piece of wood.
    CAUTION: Be careful not to deform the brake pipe during this procedure.
  4. Unlock the connector for the motor power source and disconnect the connector as shown in Fig 2 below.
    Fig 2: Sequence For Removing Motor Power Source Connector Screw
    G02605627Courtesy of SUBARU OF AMERICA, INC.
  5. Remove the 6 torx head screws (T20) which join the hydraulic unit and the ECU.
    NOTE: Do not reuse the torx head screws once removed.
  6. Remove the ECU from the hydraulic unit by pulling it gently.
    NOTE:
    1. Do not insert anything into the gap between the ECU and the hydraulic unit.
    2. Do not pry the ECU, but pull it straight from the hydraulic unit.
    3. Do not reuse the seal from the ECU.
    Fig 3: Removing ECU From Hydraulic Unit
    G02605628Courtesy of SUBARU OF AMERICA, INC.

Installation of new ECU

  1. Confirm that the sealing surface of the hydraulic unit is clean.
    NOTE:
    1. Do not machine the sealing surface.
    2. If the sealing surface is damaged, replace not only ECU but also the hydraulic unit and the ECU assembly with new one.
    3. Clean dust or foreign material from the sealing surface with a clean cloth and alcohol.
    4. Do not blow compressed air onto the ECU surface or the hydraulic unit.
  2. In order to prevent damage on the valves  protruded from the hydraulic unit, do not tilt the ECU against the hydraulic unit when assembling.
  3. Install the new ECU.
  4. Temporarily tighten 6 screws by hand.
    NOTE: Do not reuse the screws that were previously removed from the ECU.
  5. Tighten the 6 screws in the exact order shown in Fig 2 ; use the specified tightening torque of 2.65 +/- 0.30Nm (1.95 +/- 0.22ft-lbs) (26.4 inch-lbs).
  6. Check if the screws are securely tightened by confirming no clearance between ECU and hydraulic unit visually.
  7. Connect the motor power source connector to ECU.
    NOTE: Confirm that you hear a clicking sound when locking the connector lock.
  8. Install the hydraulic unit and the ECU assembly onto the bracket and tighten the two nuts with a tightening torque of 18 +/- 5Nm (13.28 +/- 3.69ft-lbs) (44.28 inch-lbs).
    NOTE: Attach the damper under the hydraulic unit with the hydraulic unit and the bracket securely.
  9. Reconnect the ECU harness connector with the ECU.

Restoration of surrounding parts

  1. Install the air cleaner case.
  2. Install the air intake duct.
  3. Connect the negative terminal to the battery.

Testing after replacement

  1. Confirm that the ABS warning lamp light comes on on normally and then turns off when the ignition switch is turned on.
  2. Connect the select monitor and confirm in the first display that the model year, driving system and transmission system are correct.
  3. Confirm that the ABS warning lamp does not light when starting the engine and driving up to more than 12.5 m/h (20 km/h).
    NOTE: If something abnormal was found in above three testing procedures, follow the repair instructions described in the diagnostic procedures of the vehicle's Service Manual.

CLAIM REIMBURSEMENT/WARRANTY INFORMATION

For vehicles within the warranty period, this repair can be claimed using the following warranty information:

CLAIM REIMBURSEMENT/WARRANTY INFORMATION

LABOR DESCRIPTION LABOR OPERATION FAIL CODES LABOR TIME
ABS Testing and Diagnosis B 566-001 0.5
ABS Electronic Control Unit C 536-101 UCD 39, 40, 41,42, or 43 1.0
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