Check for Intermittent Problems

CHECK FOR INTERMITTENT PROBLEMS

HINT: Hand-held tester only: Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect with the hand-held tester 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.

a. Clear DTCs.
b. Switch the ECM from normal mode to check mode using the hand-held tester.
c. Perform a simulation test.
d. Check and wiggle the harness(es), connector(s) and terminal(s).