Removal & Installation
Some ECM models use a CAL-PAK as well as a PROM. See Fig 1. If replacing ECM, remove CAL-PAK from old ECM and install in new ECM. Removal and replacement procedures for CAL-PAK are same as for PROM. See PROGRAMMABLE READ-ONLY MEMORY (PROM) under IGNITION SYSTEM. If units are improperly installed, grounding diagnostic test lead will set Code 52.