Diagnostic Aids

The scan tester cannot help diagnose a Code 42 problem. See INTERMITTENTS in TESTS W/O CODES article in this section.

Fig 1: CODE 42, Schematic, Elec. Spark Timing (V8 C, K & P Series W/ M/T)

Fig 2: CODE 42, Schematic, Elec. Spark Timing (All Models W/ 4L60E Trans. Exc. CPI)

Fig 3: CODE 42, Schematic, Elec. Spark Timing (All W/ 4L60E Trans. & CPI)

Fig 4: CODE 42, Schematic, Elec. Spark Timing (All W/ 4L80E Trans.)

Fig 5: CODE 42, Flowchart, Elec. Spark Timing