Engine Control Module: Service and Repair

SERVICE OF THE ELECTRONIC CONTROL MODULE (ECM)
Service of the ECM consist of replacement of ECM only. If the diagnostics call for replacement of the ECM, it will be necessary to program the Electrically Erasable Programmable Read Only Memory (EEPROM) in the ECM using the following procedure.

NOTE: It is important to transfer the broadcast code and production ECM number to the service ECM label. Please do not record on ECM cover. This will allow positive identification of ECM parts throughout the service life of the vehicle.

CAUTION:
^ To prevent internal ECM damage, the ignition must be "OFF" when disconnecting or reconnecting power to ECM (for example; battery cable, ECM pigtail, ECM fuse, jumper cables,).
^ To prevent possible electrostatic discharge damage to the ECM, Do Not touch the connector pins or soldered components on the circuit board.

REMOVAL
1. Disconnect the negative battery cable.
2. Remove the two (2) 10 mm nuts at ECM.
3. Disconnect the connectors from ECM.
4. Remove the ECM from mounting bracket.
5. Remove the ECM from driver's compartment.

INSTALLATION
1. Install the mounting bracket to the ECM.
2. Connect the ECM connectors to ECM.
3. Two (2) 10 mm nuts and tighten to 2.2-3.4 Nm (17-30 in lb).
4. Connect the negative battery cable.
5. Proceed to EEPROM programming.

Electrically Erasable Programmable Read Only Memory (EEPROM) Programming
1. Setup:
^ Battery is charged.
^ Ignition in "ON."
^ Connect directly to battery using a suitable -adapter.
^ Data Link Connector (DLC), formerly "ALDL" must be secure.
2. Refer to up-to-date Techline terminal/equipment user's instructions.
3. If ECM fails to program, do the following:
^ Check all ECM connections.
^ Check Techline terminal/equipment for latest software version.
^ Try again to program the ECM. If it fails again, replace the ECM. Replacement ECM must be programmed.
4. Drive vehicle so as to allow the Idle Air Control (IAC) valve to reset.
5. If vehicle is equipped with an anti-theft system, it may require a reset procedure.

NOTE: A mis-programmed ECM any cause the "ECONO" light on the 1.8L DOHC to flash all the time.

CAUTION: The ignition should always be "OFF" when installing or removing the ECM connectors.

FUNCTIONAL CHECK
Use Techline terminal/equipment to perform the "On-Board Diagnostic OBD System Check," or refer to Computers and Controls / System Diagnosis / Procedures / Diagnostic System Check.