Check For Intermittent Problems
CHECK FOR INTERMITTENT PROBLEMSHINT: Hand-held tester only:
Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect with a hand-held tester when the ECM is in check mode. In check mode, the ECM uses 1trip 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 a hand-held tester
c. Perform a simulation test
d. Check and wiggle the harness(es), connector(s) and terminal(s)