Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

2003 GMC Yukon - Low Power Mode, Service 4ws, Service Brake

lo power mode dtc code p1518 service 4wd servicebrake system all show up on any bump

3 distinctly different problems needing repair…

Bad throttle body actuator, likely a bad 4WD switch and low brake fluid, maybe.

Since all of these warnings appear whenever you hit a bump, I wonder if a connection in the wiring harness could be loose? Just a thought…