Intermittent Diagnosis

Intermittent problems are the most difficult to diagnose. There are 3 different methods used to help diagnose intermittent concerns. These methods provide techniques to help resolve these issues without wasting time or unnecessarily replacing components. These methods are as follows:

• Determine Repeatability Of DTC
  
  This procedure helps to separate repeatable conditions from intermittent conditions. This procedure is used at the start of each DTC or PINPOINT test. See appropriate test.
• Drive Test
  
  Perform a drive test under specific conditions aimed at reproducing the intermittent. Drive vehicle under varied engine temperature (cold-hot) while driving over bumpy roads to provide vibration to components, connections and wiring.
• Wiggle Test
  
  Wiggling wiring harness and connectors and vibrating components while monitoring for a change of state using New Generation Star (NGS) tester. When a change of state occurs, an audible tone can be heard and/or the intermittent DTC will be reproduced.