Ignition System - C3I: Testing

The C(3)I ignition system is an integral part of the engine's computerized engine control system. Refer to 3800 ECM TESTS/CODES article in the COMPUTERIZED ENGINE CONTROLS section for appropriate testing and diagnosis information.

If engine cranks but will not run or if it stalls, CHART A-3 must be used to determine if failure is in the C(3)I ignition system or fuel injection system.

If either Code 41 or Code 42 (E041 or E042 on some models) is set, use appropriate chart for proper diagnosis. If symptom is an engine miss and the C(3)I ignition system is suspected, CHART C-4F must be used.