Circuit Description
WARNING: This page is about a different car, the 1999 Pontiac Grand Am and 1999 Oldsmobile Alero. However, it is still accessible from the selected car via links, so may be relevant.
DTC B1492 determines if a fault exists that causes the generator PWM reading to be continuously LOW. DTC B1492 will set in the IPC when the PCM is sending ENGINE-IS-RUNNING class 2 serial data, the FIELD TERMINAL PRESENT calibration is enabled in the PCM, PCM is sending class 2 serial data message indicating generator PWM is less than 1.96 percent and the engine is running at 3000 RPM or less for 30 seconds. DTC B1492 will set and the IPC will turn on the charge indicator light. The IPC history codes will be cleared after 100 ignition cycles with no current DTCs present throughout duration.