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Home >> GMC >> 1995 >> Forward Control 4.3 Z, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 6.5L Diesel. >> Diagnostic Trouble Code Charts >> DTC 51, Prom Problem (Faulty Or Incorrect Prom)
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DTC 51, Prom Problem (Faulty Or Incorrect Prom)

PROM PROBLEM (FAULTY OR INCORRECT PROM)

Ensure all pins are fully inserted in socket. If pins are fully inserted, replace PROM, clear memory and recheck. If DTC 51 resets, replace PCM. If PCM is faulty and must be replaced, TDC OFFSET must be programmed into new PCM. When all diagnosis and repairs are complete, clear DTCS and verify for proper operation.