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SERIES 40E ECM

The ECM wiring harness removal and installation procedures follow. ‪

ECM Removal

Remove the ECM as follows: ‪

  1. Disconnect batteries.
  2. Remove screws and connector cover shields from the ECM connector covers, see Figure 31139 .

    1. Connector Shield Screw ‪

    3. Connector Cover ‪

    2. Connector Shield ‪

    4. Wiring Harness Connector ‪

    ECM Connector Cover Removal

  3. Remove ECM connector covers, see Figure 31139 , from the wiring harness connectors.

    1. Connector Shield Screw ‪

    3. Connector Cover ‪

    2. Connector Shield ‪

    4. Wiring Harness Connector ‪

    ECM Connector Covers

  4. Loosen the chassis wiring harness connector mounting bolt and remove wiring harness from the ECM.
  5. Loosen engine wiring harness connector mounting bolt and disconnect engine wiring harness from the ECM; see Figure 31140 , and see Figure 31156 .

    1. ECM ‪

    2. Engine Wiring Harness Connector ‪

    Engine Wiring Harness

    Note: If it is not necessary to remove the ECM from the mounting bracket, refer to step .

  6. Remove the ECM wiring harness connector gaskets from the ECM unit. See Figure 31156 .

    1. ECM ‪

    2. Engine Wiring Harness Connector ‪

    Remove Engine Wiring Harness

  7. If it is necessary to remove the ECM from the mounting bracket, remove the four ECM mounting bolts and lift the ECM from the bracket, see Figure 31238 , and see Figure 31239 .

    1. ECM Mounting Bolts ‪

    2. Front Mounted ECM ‪

    Front ECM Unit

  8. Remove the bottom mounting bolts of the ECM mounting bracket, see Figure 31239 .

    1. Rear Mounted ECM ‪

    2. ECM Mounting Bolts ‪

    Rear ECM Unit

  9. Remove the three top mounting nuts of the ECM mounting bracket and lift bracket away from engine, see Figure 31264 .
  10. If required, remove bushings and pins from mounting bracket, see Figure 31264 .

    1. Bushings and Pin Location ‪

    3. ECM Mounting Bracket ‪

    2. ECM Mounting Bracket Nuts ‪

    ECM Bushings, Pins and Nuts

ECM Inspection

Inspect ECM mounting bushings and pins for cracks, cuts, worn spots, etc. Replace as required, see Figure 31272 . ‪

1. Bushings ‪

2. Pin ‪

ECM Bushings and Pin

Inspect the engine wiring harness connectors, connector covers, and cover shields for cracks, cuts or worn areas. Replace as required, see Figure 31288 . ‪

1. Wiring Connector Cover ‪

4. Wiring Harness Connector ‪

2. Connector Cover Shield ‪

5. ECM Gasket ‪

3. Screw ‪

Connector Cover Parts

Installation of ECM and Mounting Bracket as a Single Unit

Installation procedures for the front mounted or rear mounted ECM are identical, except where noted. The ECM and mounting bracket are installed as a single unit. ‪

  1. Install the ECM and mounting bracket to the engine. Torque the three top mounting nuts to the specification, see Figure 31271 . Refer to section , Specifications.

    1. ECM ‪

    3. ECM Mounting Bracket Nuts ‪

    2. ECM Mounting Bracket ‪

    ECM Bushings, Pins and Nuts

  2. Install the two (2) bottom bolts for the mounting bracket and torque to the specification; see Figure 31240 . Refer to section , Specifications.

    Bottom ECM Bracket Bolts

  3. Install the two ECM gaskets into the ECM connector receptacles.

    NOTICE:

    Do not use bearing grease or other non-dielectric grease on the ECM connectors as this may result in improper terminal contact and inefficient ECM operation. ‪

  4. Apply a 3/8 in. bead of quality dielectric grease, such as Navistar P/N 1831731C1 or equivalent, to the ECM wiring harness connector. Use approximately 1/4 ounce of dielectric grease on the connector. Begin applying grease from the bolt, and move toward the ends of the ECM connector. See Figure 40225 .

    Note: Dielectric grease P/N 1831731C1 is available from authorized Navistar parts distributors. It is not marketed by Detroit Diesel parts distributors.

    1. Location of Dielectric Grease ‪

    Application of Dielectric Grease to ECM Harness Connector

  5. Install the connector into the ECM. The dielectric grease will coat the terminals and overflow the sides of the connector, producing a moisture-tight seal.
  6. Connect the engine wiring harness, see Figure 31140 , to the ECM and torque the connector retaining screw to the specification. Refer to section , Specifications.

    1. ECM ‪

    2. Engine Wiring Harness Connector ‪

    Install Engine Wiring Harness

  7. Apply a 3/8 in. bead of quality dielectric grease to the ECM wiring harness connector. Use approximately 1/4 ounce of dielectric grease on the connector. Begin applying grease from the bolt, and move toward the ends of the ECM connector. Connect the second wiring harness to the ECM and torque the connector retaining screw.
  8. Install the ECM connector covers, see Figure 31139 , over the wiring harness connectors.

    1. Connector Shield Screw ‪

    3. Connector Cover ‪

    2. Connector Shield ‪

    4. Wiring Harness Connector ‪

    Install ECM Connector Covers

  9. Place the connector shields onto the connector covers and secure with the connector cover shield screw, see Figure 31264 .

    1. ECM Mounting Bracket ‪

    3. ECM Mounting Bracket Nuts ‪

    2. Bushings and Pin Location ‪

    ECM Bushings, Pins and Nuts

  10. Connect the batteries.

Installation of ECM and Mounting Bracket as Separate Units

Installation procedures for the front mounted or rear mounted ECM are identical, except where noted. The ECM and mounting bracket are installed separately. ‪

  1. Install the four pins and eight mounting bushings into the mounting bracket. See Figure 31240 .

    Bottom ECM Bracket Bolts

  2. Install the mounting bracket to the engine. Torque the top three mounting bolts. See Figure 31240 . Refer to section , Specifications.
  3. Install the two bottom bolts for the mounting bracket and torque. See Figure 31240 . Refer to section , Specifications.

    Bottom ECM Bracket Bolts

    NOTICE:

    Do not use bearing grease or other non-dielectric grease on the ECM connectors as this may result in improper terminal contact and inefficient ECM operation. ‪

  4. Apply a 3/8 in. bead of quality dielectric grease, such as Navistar P/N 1831731C1 or equivalent, to the ECM wiring harness connector. Use approximately 1/4 ounce of dielectric grease on the connector. Begin applying grease from the bolt, and move toward the ends of the ECM connector. See Figure 40225 .

    Note: Dielectric grease P/N 1831731C1 is available from authorized Navistar parts distributors. It is not marketed by Detroit Diesel parts distributors.

    1. Location of Dielectric Grease ‪

    Application of Dielectric Grease to ECM Harness Connector

  5. Install the connector into the ECM. The dielectric grease will coat the terminals and overflow the sides of the connector, producing a moisture-tight seal.
  6. Install the front mounted ECM onto the mounting bracket and torque the four mounting bolts. See Figure 31238 . Refer to section , Specifications.

    1. Front Mounted ECM ‪

    2. ECM Mounting Bolts ‪

    Install Engine Wiring Harness

  7. Install the rear mounted ECM onto the mounting bracket and torque the four mounting bolts; see Figure 31239 . Refer to section , Specifications.

    1. Rear Mounted ECM ‪

    2. ECM Mounting Bolts ‪

    Install ECM Connector Covers

  8. Install the two ECM gaskets into the ECM connector receptacles.
  9. Apply a 3/8 in. bead of quality dielectric grease to the ECM wiring harness connector. Use approximately 1/4 ounce of dielectric grease on the connector. Begin applying grease from the bolt, and move toward the ends of the ECM connector. Connect the engine wiring harness to the ECM, see Figure 31156 .

    1. Connector Shield Screw ‪

    3. Connector Cover ‪

    2. Connector Shield ‪

    4. ECM Unit ‪

    Install ECM Connector Covers

  10. Torque the connector retaining screw; see Figure 31265 . Refer to section , Specifications.

    Securing ECM Connector

  11. Install and connect the second wiring harness to the ECM. Torque the connector retaining screw. Refer to section , Specifications.
  12. Install the ECM connector covers over the wiring harness connectors. See Figure 31139 .

    1. Connector Shield Screw ‪

    3. Connector Cover ‪

    2. Connector Shield ‪

    4. Wiring Harness Connector ‪

    Install ECM Connector Covers

  13. Place the connector shields onto the connector covers and secure with the connector cover shield screw. See Figure 31139 .
  14. Connect the batteries.