ECM/PCM - Potential MEM-CAL Damage

91cadillac06

Bulletin No.: T-91-95
File in Group: 6E
Number: 88
Corp. Ref. No.: 176502R
Date: June, 1991


SUBJECT:
POTENTIAL DAMAGE WHEN INSTALLING AN ECM/PCM MEM-CAL

MODELS AFFECTED:
ALL 1986-1991 MODELS WITH MEM-CAL


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 vehicle's original equipment ECM/PCM.

Excessive vertical force may be applied to the MEM-CAL resulting in flexing of the circuit board and damage to 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.

To repair this condition use the following procedure:

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

1. Inspect the MEM-CAL to determine if a cork spacer is glued to the top side of the MEM-CAL assembly. If so, remove it 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 unit 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 the 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.