ECM/PCM - Damage Prevention

9218oldsmobile06

NUMBER: 91-T-139

CORP.REF.NO: 176502R

DATE: June 1991

SECTION: 6E3


SUBJECT:
DAMAGE TO ECM/PCM CIRCUIT BOARD WHEN INSTALLING A MEM-CAL NEW MEM-CAL INSTALLATION PROCEDURE

MODELS/YEARS:
ALL 1986-91 MODELS WITH MEM-CAL


CONDITION: When installing a service replacement ECM/PCM, the use of incorrect MEM-CAL installation procedures may cause the ECM/PCM to fail before it can be installed in the vehicle. This condition may appear as if the ECM/PCM were defective when it was shipped to the dealership, when in fact it was damaged while being installed. In addition this condition may also occur when installing an "updated" service MEM-CAL into the vehicles original equipment ECM/PCM.

CAUSE: Excessive vertical force may be applied to the MEM-CAL resulting in flexing of the circuit board damaging the connections between the circuit board and attached components. Excessive vertical force may be generated in two ways.

1. Incorrect MEM-CAL installation procedure.

2. Interference between MEM-CAL and cover.

CORRECTION: Use the following Service Procedure.

Important: This procedure supersedes any instructions regarding MEM-CAL installation dated prior to September 1990.

1. Inspect the MEM-CAL to determine d a cork spacer is glued to the MEM-CAL assembly or cover. If so, remove the cork spacer prior to installation.

2. Align small notches with matching notches in the ECM/PCM MEM-CAL socket.

3. Very gently press down on the ends of the MEM-CAL until the locking levers are rotated toward the sides of the MEM-CAL

Notice: To avoid ECM/PCM damage, do not press on the ends of the MEM-CAL until the levers snap into place. Do not use any vertical force beyond the minimum required to engage the MEM-CAL into its socket.

4. While continuing light pressure on the ends of MEM-CAL, use your index fingers to press the locking levers inward until they are snapped into place. Listen for click.

5. Install MEM-CAL cover and Install ECM/PCM in vehicle.