Some jobs, such as brake bleeding and changing the hybrid system coolant, require a scan tool to run the pump. However most maintenance is straightforward – once you've taken the proper precautions.
Before beginning any job, make sure the vehicle has been turned off and disable the Smart Key by pushing the button below the steering wheel; pushing in disables it. If the word "Ready" appears on the instrument panel display, the vehicle is not turned off and the engine could start at any time. Also, using heavy rubber gloves, disable the high-voltage system by removing the large orange service plug next to the spare tire. For added safety, keep the plug in your pocket.Like many Toyotas, valve adjustment requires removing the camshafts to install different thickness lifters. With regenerative braking doing most of the work, Prius wheel brakes don't get used much. Check the brakes at each oil change and look for rusty rotors and delaminated brake pads.
There are two complete cooling systems. The engine's system has an insulated reservoir behind the left headlight that can stay hot up to four days, so be careful when opening the drain cock. Toyota does not list a quantity for the hybrid system coolant, so follow service manual instructions for changing/bleeding/refilling. Because so many systems are unique to this vehicle, use of the correct fluids is critical. Even using the wrong oil viscosity can set a diagnostic trouble code (DTC).There are a number of technical service bulletins (TSBs). Most, such as malfunction indicator lamp (MIL) illumination with DTC P3009 requiring replacement of the Power Inverter (Hybrid System) or any code with P0AXX are for the hybrid system. These are probably covered under an extended warranty.
Failure to properly latch the high-voltage service plug will cause MIL illumination with DTC P3140 or P3141. Ignition codes can be caused by water leaking past the cowl cover.
