PCM Replacement

If the powertrain control module (PCM) is replaced, the following procedures must be performed:

1. The PCM Reprogramming-Refer to Service Programming System (SPS) .
2. The CKP Variation Learn-Refer to the appropriate procedure:
   • Crankshaft Position System Variation Learn for the 4.3L (LU3) engine.
   • Crankshaft Position System Variation Learn for the 4.8L, 5.3L, 6.0L (LR4, LM7, LQ4, LQ9, or L59) engine.
   • Crankshaft Position System Variation Learn for the 8.1L (L18) engine.
3. The Theft Deterrent Programming-Refer to Programming Theft Deterrent System Components .
4. The Fuel Composition Diagnostic-Refer to Fuel Composition Diagnosis for the 5.3L (L59).