R2 Check Rear Axle Outlet Valve

- Key OFF.

- Install Rotunda(r) Breakout Box 014-00322 or equivalent. Using the Breakout Box For Circuit Checks

- Jumper Pins 19, 27, 33, and 1 together on the Rotunda(r) Breakout Box 014-00322 or equivalent.

- Raise vehicle so rear wheels are just off the ground.

- Press hard on the brake pedal and have an assistant try to turn a rear wheel.

- Does the wheel turn or the brake pedal drop slowly?

NOTE: This condition is similar to the master cylinder bypass condition. It is important that the pedal be quickly and forcefully applied to rule out master cylinder bypass as the cause if a hydraulic leak is detected. Typically, master cylinder bypass only occurs at low line pressures.

YES -- Replace HCU. Perform brake bleeding procedure.

NO -- GO to R3. R3 Check Rear Axle Outlet Valve Operation