Isolate the Problem

Isolate The Problem

To isolate the problem is "to place apart from others".
The object here is to zoom in on the problem area. It is easy to be overwhelmed by a problem, just reaching for an ETM can add to the confusion. The DISplus provides automatic tests in test modules to aid in the determination of the exact area or cause of the problem.

The elimination of components from the diagnostic trail, shortens the path. The first question asked should be:
- Is the problem Hydraulic, Mechanical or Electrical?

Save time by NOT testing components that could not create the problem.

Steps in Isolating The Problem
- Use Test Modules.
- Perform electrical tests with the DISplus Measurement System or a DVOM.
- Consult fault charts in Repair or Diagnostic Procedures Manuals.
- Control Module Self Diagnosis.
- Use appropriate special tools (e.g. battery draw tester, tank leakage adapters, breakout boxes, etc.).
- Substitute a known good part.

Workshop Hints:

If a TEST PLAN is not available for a particular situation do the following:
- Think about the system in its entirety.
- Be sure the normal operation is understood.
- Develop a PLAN.
- Use all available resources.
- Don't try to diagnose the entire system at once, break it into manageable chunks.
- Check the easy things first. It would waste time to install the Breakout Boxes to find a bad bulb.

When following a TEST PLAN:
- DON'T Skip steps.
- NEVER assume results without doing a step.
- Recheck your work.