Engine Control Module: Service and Repair

Electronic Calibration Unit (MEM-CAL):

CAUTION: To prevent possible electrostatic discharge damage to the ECM or MEM-CAL, do not touch connector pins or soldered circuit components. The ignition must always be "OFF" when disconnecting or reconnecting power to the ECM.


Service of the ECM normally consists of either ECM or MEM-CAL replacement. If diagnostic procedures call for ECM replacement, check the electronic calibration unit (MEM-CAL) and ECM first to ensure that they are the correct parts. If they are, remove MEM-CAL from faulty ECM and install in new service ECM unit. The service ECM will not contain a MEM-CAL.

REPLACE MEM-CAL

MEM-CAL Removal:

1. Disconnect battery negative cable.
2. Remove ECM from vehicle.
3. Remove ECM access cover.
4. Using two fingers, push both retaining clips away from MEM-CAL at the same time. Grasp MEM-CAL at both ends and lift it from its socket.

MEM-CAL Installation:

5. Install replacement MEM-CAL in the socket and seat by pressing on the ends. Do not press in the middle. Inspect MEM-CAL pins for damage before installation.
6. Push the retaining clips into the side of the MEM-CAL until they snap into place with an audible "click."

MEM-CAL Alignment Notches:

NOTE: The small notches in the MEM-CAL unit must align with the small notches in the socket.