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Home >> Buick >> 1995 >> LeSabre Custom >> Repair and Diagnosis >> External Pages >> Different car >> Section 5 (Engine Controls - Tests W/Codes) >> ECM/Pcm Code Charts >> Code P1568, Cruise System Problem (SPS Indicated High) >> Circuit Description

Circuit Description

WARNING: This page is about a different car, the 1995 Oldsmobile Ninety-Eight and 1995 Buick Park Avenue. However, it is still accessible from the selected car via links, so may be relevant.

PCM controlled cruise control system is designed to be self monitored to ensure desired cruise servo position and actual cruise servo position are equal to one another. When Code P1568 is set, vehicle may operate in power management mode and Code P1599 will set. While in power management, PCM will shut off fuel to 3 cylinders to avoid over-revving engine in case throttle is being held open by a sticking cruise control throttle cable, brake vacuum release valve, or cruise control servo. Power management may be perceived as a severe engine miss or lack of power.