- Block the wheels.
- Start the engine. Charge the system to the air compressor governor cutout
point.
- Stop the engine.
- Shift the two speed rear axle shift control valve to HIGH. Verify that
air pressure is present in the entire system.
- Inspect for air leaks using a soap solution. Repair any air leaks. Refer
to
Air Brake System Testing
in Air Brakes.
- Shift the two speed rear axle shift control valve to LOW.
- Verify that air pressure is present ONLY up to the two speed rear axle
shift control valve. If air pressure is present in the entire system,replace the
two speed rear axle shift control valve.
- Verify that the two speed rear axle shift motor is operating properly.
| • | If the two speed rear axle shift motor is operating properly, you will
hear a definite reaction by the sound of parts moving. |
| • | If you do not hear the sound of parts moving, . |
- Remove the wheel blocks.
