Six-Step Troubleshooting Procedure

Diagnosis of the engine control module (ECM) and sentry key immobilizer system (SKREEM) is done in six basic steps:

• verification of complaint
• verification of any related symptom
• symptom analysis
• problem isolation
• repair of isolated problem
• verification of proper operation
  NOTE: All tests in this article should be performed with the engine at operating temperature, unless otherwise specified within a particular test.