Toyota Tundra Service Manual: Check For Intermittent Problems

CHECK FOR INTERMITTENT PROBLEMS

HINT:

Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect with the Techstream when the ECM is in check mode. In check mode, the ECM uses 1 trip detection logic, which is more sensitive to malfunctions than normal mode (default), which uses 2 trip detection logic.

  1. Clear the DTCs (See page ).
  2. Switch the ECM from normal mode to check mode using the Techstream (See page ).
  3. Perform a simulation test.
  4. Check and wiggle the harness(es), connector(s) and terminal(s).
    Brake Override System

    Check Mode Procedure

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