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Home >> Cadillac >> 1987 >> Seville >> Repair and Diagnosis >> Engine Performance >> System >> DFI Components Removal & Installation (4.1L) >> Removal & Installation >> BCM Programmable Read Only Memory (Prom) >> Installation
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BCM Programmable Read Only Memory (Prom): Installation

  1. Place new PROM in carrier upside-down on flat surface (pins facing up). Using a narrow blunt tool, press PROM body down on both sides of retainer bar so top of the PROM is flush with the top of the PROM carrier.
  2. Position PROM carrier squarely over PROM socket in BCM. Firmly press down on top of carrier. Alternately pressing down on either end of carrier will securely seat PROM. Install PROM access cover. Install BCM in vehicle.
  3. Perform PROM functional check: Turn ignition on. If any of the following conditions result, check PROM for proper orientation, bent or broken pins, and complete insertion.
    • Climate Control Panel displays "B151" and no key response.
    • Fuel Data Center is blank and no key response.
    • A/C compressor is disabled.
    • Heater-Vent-Air Conditioning (HVAC) in defrost mode with blower on high.
    • No BCM-to-ECM data communication.
    • Vacuum fluorescent display dimming, parking lamps on, commanded to full brightness.
  4. If not fully seated, remove access cover and press firmly on carrier. If pins are bent, remove PROM, straighten pins and reinstall. If pins break or crack during straightening, replace PROM. If PROM was installed backwards, it must be replaced.