Circuit Description

1998 Oldsmobile Achieva 3.1 M, 4T40E/MN4SECTION Circuit Description

Ignition Control Module (ICM) sends signals that PCM requires for fuel control and spark advance calculations. At start of engine crank, ICM controls spark advance (by-pass mode). When second 3X signal is recognized by PCM, it applies 5 volts to by-pass circuit, commanding ICM to switch Ignition Control (IC) of spark advance to PCM (IC mode). A short in IC circuit, or an open or short ground in by-pass circuit will set DTC 1361.

Condition required to set DTC is:

  • PCM senses IC pulses during crank while by-pass mode spark advance is commanded.
  • Engine speed greater than 600 RPM.
  • DTC P1350 not set.
RENDER: 1.0x

NO RELATED

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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