P0574

P0574 is a generic cruise control system fault that the PCM sets when it detects an unexpected state on the cruise input network, most commonly disagreement between the brake switch, the cruise on/off switch, and the set/resume input. Start cheapest: clear the code and try to engage cruise on a flat road above the minimum activation speed; if it refuses to set, scan live data for Brake Switch, Cruise On/Off, and Cruise Set PIDs and watch each one toggle as you operate the controls. A stuck-on brake switch input will set P0574 because cruise cannot engage with brakes apparently applied; this is the single most common root cause. Caveat: do not replace the cruise control module or ECM until the brake switch input has been verified clean on a scan tool, because the brake switch is the upstream input and a bad switch will keep setting P0574 forever.

Vehicle-specific patterns: 2007 to 2013 GM trucks and SUVs set P0574 as a companion code to P0572 because the integrated brake switch feeds both circuits. 2005 to 2010 Ford F-150, Expedition, and Lincoln Navigator with the 5.4L Triton suffer from the cruise control deactivation switch on the master cylinder failing and triggering P0574, which was part of the massive Ford cruise-switch recall over fire risk. 2008 to 2014 Subaru Legacy, Outback, and Forester set P0574 when the brake light switch contacts oxidize, particularly in cold climates. 2009 to 2015 Honda Pilot and Odyssey with the steering-wheel cruise buttons exhibit clockspring wear that sets P0574 intermittently when the wheel is turned. Estimated repair: $50 to $450.