LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 1995 >> Forward Control 7.4 N >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 10 (Engine Controls - Remove/Install/Overhaul - 4.3L) >> Powertrain Control Module (Pcm) >> Programmable Read-Only Memory (Prom) >> Installation
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Programmable Read-Only Memory (Prom): Installation

WARNING: This page is about a different variant/trim than selected.
  1. Ensure new PROM has same service number as old one or correct factory upgrade. Place NEW PROM in PROM carrier, and position squarely over PCM PROM socket. Press on PROM carrier until PROM is firmly seated in PCM.
    NOTE: Ensure reference notches in PCM and PROM are properly aligned. If PROM is installed backwards and ignition is turned on, PROM will be destroyed.
  2. Install PROM access cover on PCM. Install PCM in vehicle. See INSTALLATION under CONTROL MODULE . Turn ignition on and ground DLC terminal "B". Check for DTC 51.
  3. If DTC 51 is present, PROM is not fully seated in PCM, installed backwards, has bent pins, or is defective. If bent pins are cracked while straightening, replace PROM. If PROM is installed backwards or is defective, replace PROM.
Fig 1: Locating PROM On PCM
G95J27432Courtesy of GENERAL MOTORS CORP.
scientia non olet · About LEMON Manuals