Engine Control Module, Removing and Installing

Engine Control Module, Removing and Installing

Special tools, testers and auxiliary items required

• Heat gun.

Removal

- Remove the rubber seal - 1 - for plenum chamber cover- 2 -.

- Remove plenum chamber cover - 2 -.





- Remove the windshield wiper arm caps.

- Loosen the wiper arm nuts - arrows -.





- Remove the wiper arms by rocking slightly with an up and down motion.

- Remove the wiper arm nuts and wiper arms.

• If wiper arms cannot be removed, use a standard puller.

- Remove cowl grille screws - arrows -.

- Remove the cowl grille - 1 - from the windshield.





- Remove the screws - 1 and 3 - and dome braces - 2 - if equipped.





- Remove the screws - arrows - and E-box cover.





- Using a screwdriver- arrows 1 and 2 -, remove the retaining clip - 3 - and Engine Control Module (ECM) (J623) from E-box.





• 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 the 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 => [ Engine Control Module, Replacing ] Engine Control Module, Replacing