Check For Intermittent Problems

WARNING: This page is about a different car, the 2006 Scion tC. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Intelligent tester only:

Inspect the vehicle's ECM using check mode. Intermittent problems are easier to detect with a intelligent 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.

Clear DTCs (see DTC CHECK / CLEAR ).
Switch the ECM from normal mode to check mode using a intelligent tester (see CHECK MODE PROCEDURE ).
Perform a simulation test (see HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS ).
Check and wiggle the harnesses, connectors and terminals (see HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS ).