Circuit Description

1998 Oldsmobile Achieva 3.1 M, 4T40E/MN4SECTION Circuit Description
WARNING: This page does not describe the selected car, but rather 65 other vehicles, including the 1999 Saturn SW2, 1999 Saturn SW1, 1999 Saturn SL2, 1999 Saturn SL1, and 1999 Saturn SL. However, it is still accessible from the selected car via links, so may be relevant.

The PCM output "L" terminal to alternator determines when generator will be turned off. It is on under all normal vehicle operating conditions except during low RPM conditions. Generator is turned off during low RPM conditions to remove excess load from engine. The generator warning light will illuminate anytime ignition is on and engine is not running. The warning light will turn off after engine is running and generator is putting out the desired amperage. DTC will set when engine is running, generator warning light is on, and generator "L" terminal voltage is low while PCM is commanding the generator on and condition is present for more than 30 seconds.

RENDER: 1.0x

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When to See a Mechanic

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

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
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