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Programmable Read-Only Memory: Installation

  1. Ensure new PROM has same service number as original or is 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.
    CAUTION: 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 POWERTRAIN CONTROL MODULE . Start engine and enter diagnostics. See appropriate TESTS W/CODES article. Check for diagnostic trouble codes. See appropriate TESTS W/CODES article for code identification.
  3. If code(s) sets, PROM is either not fully seated in PCM or installed backward, has bent pins or is defective. If bent pins crack when trying to straighten, replace PROM. If PROM is installed backward or is defective, replace PROM.