Engine Control Module, Removing and Installing

Engine Control Module, Removing and Installing

Engine management on the 5.2L 10-cyl 4V BXA is controlled by two Engine Control Modules (ECM), the Engine Control Module (ECM) (J623) (master) and the Engine Control Module (ECM) 2 (J624).

The Engine Control Module (ECM) (J623) (master) communicates which functions need to performed by the Engine Control Module (ECM) 2 (J624) (slave).

The Engine Control Modules (ECM) communicate through CAN-Bus.

Engine Control Module

Special tools, testers and auxiliary items required

• Heat gun.

Removal

- Remove the rubber seal from the plenum chamber cover - 1 -.

- Remove the plenum chamber cover - 2 -.

• The Engine Control Modules (ECM) are identical. If both Engine Control Modules (ECM) are removed, they must be marked before removal to prevent them from being interchanged when re-installing.

• Engine Control Module (ECM) (J623) (master) - 2 -: "M".

• Engine Control Module (ECM) 2 (J624) (slave) - 1 -: "S".

- Remove the Engine Control Module (ECM) (J623) (master)- 2 -.

• The Engine Control Module (ECM) (J623) - 1 - is secured to a protective housing - 2, 5 - with shear bolts - 3, 4 -.

• To disconnect the electrical harness connectors from the Engine Control Module (ECM) (J623) (e.g. to connect the test box or to replace the ECM), the protective housing - 2, 5 - must be removed.

• The threads of the shear bolts - 3 - are coated with a locking compound to make removal more difficult and must be heated prior to removal.

CAUTION!
The shear bolts that are screwed into the Engine Control Module (ECM) (J623), are not coated with a locking compound and do not require heating. Do not heat the Engine Control Module (ECM) (J623) or damage to the Engine Control Module (ECM) (J623) may occur.

To avoid damage (burning) of wire connections and harness connectors, insulation and control modules, the following work steps must be adhered to exactly! Observe operating instructions for heat gun.

CAUTION!
After heating, parts are extremely hot. To prevent personal injury, avoid touching the protective housing after heating the shear bolts and surrounding area.

- Using a Heat gun set at its lowest setting, heat the shear bolt for approx. 20 to 25 seconds.

- Remove the shear bolt with locking pliers. Discard the used shear bolts.

Repeat the previous steps for the second shear bolt.

- Remove the protective housing from the Motronic Engine Control Module (ECM) (J623).

• Adaptation values are erased when the connectors are disconnected from the Motronic Engine Control Module (ECM) (J623), DTC memory content remains intact.

- Disconnect the electrical harness connectors from the Motronic Engine Control Module (ECM) (J623).

Installing

Installation is in the reverse order of removal. Note the following:

- The ECM must be installed with the protective housing.

- Use new shear bolts.

- Remove a thread compound from the threaded holes with a thread cutter (tap) to allow for new shear bolt installation.

After installing a new Motronic Engine Control Module (ECM) (J623), the following work steps must be performed:

- Activate the Motronic Engine Control Module (ECM) (J623). Refer to the => Ebahn website.

Engine Control Module 2

Special tools, testers and auxiliary items required

• Heat gun.

Removal

- Remove the rubber seal from the plenum chamber cover - 1 -.

- Remove the plenum chamber cover - 2 -.

• The Engine Control Module (ECM) 2 (J624) - 1 - is secured to a protective housing - 2, 5 - with shear bolts - 3, 4 -.

• To disconnect the electrical harness connectors from the Engine Control Module (ECM) (J623) (e.g. to connect the test box or to replace the ECM), the protective housing - 2, 5 - must be removed.

• The threads of the shear bolts - 3 - are coated with a locking compound to make removal more difficult and must be heated prior to removal.

CAUTION!
The shear bolts that are screwed into the Engine Control Module (ECM) 2 (J624), are not coated with a locking compound and do not require heating. Do not heat the Engine Control Module (ECM) 2 (J624) or damage to the Engine Control Module (ECM) 2 (J624) may occur.

To avoid damage (burning) of wire connections and harness connectors, insulation and control modules, the following work steps must be adhered to exactly! Observe operating instructions for heat gun.

CAUTION!
After heating, parts are extremely hot. To prevent personal injury, avoid touching the protective housing after heating the shear bolts and surrounding area.

- Using a Heat gun set at its lowest setting, heat the shear bolt for approx. 20 to 25 seconds.

- Remove the shear bolt with locking pliers. Discard the used shear bolts.

Repeat the previous steps for the second shear bolt.

- Remove the protective housing from the Engine Control Module (ECM) 2 (J624).

• Adaptation values are erased when the connectors are disconnected from the Engine Control Module (ECM) 2 (J624), DTC memory content remains intact.

- Disconnect the electrical harness connectors from the Engine Control Module (ECM) 2 (J624).

Installing

Installation is in the reverse order of removal. Note the following:

- The ECM must be installed with the protective housing.

- Use new shear bolts.

- Remove a thread compound from the threaded holes with a thread cutter (tap) to allow for new shear bolt installation.

After installing a new Engine Control Module (ECM) 2 (J624), the following work steps must be performed:

- Activate the Engine Control Module (ECM) 2 (J624). Refer to the => Ebahn website.