Operation - Section 30 OM3043 06/06 Page 30-12 Operating Instructions EMERGENCY STEERING SYSTEM Testing This test can only be performed with an empty truck. Operation 1. Ensure no one is near the front tires during this test. Use a spotter to keep the area around the front tires clear of personnel during this test. The truck is equipped with an emergency steering system. This system is a backup in the event of loss of oil supply to the main steering system. The emer- gency steering system was designed to meet or exceed SAE J1511 and ISO 5010 standards. 2. Start the engine. Allow the hydraulic system to reach full pressure and the accumulators to fill with oil.
If the low steering system pressure indicator light and alarm are activated, a failure in the hydraulic oil sup- ply to the steering and brake system exists. When the alarm is activated, typically there is enough hydraulic pressure stored in the brake and steering accumula- tors to allow brief operation of the steering and brake functions. However, this oil supply is limited. There- fore, it is important to stop the truck as quickly and safely as possible after the alarm is first activated. 3. Shut the engine off by using the engine stop button located on the center console. DO NOT turn the key switch OFF. 4. Turn the steering wheel. a.
If the front tires respond when the steering wheel is turned, the emergency steering sys- tem is functioning properly. Turn the key switch OFF. If the oil supply pressure drops to a predetermined level, the low brake pressure warning light will also illuminate. If the oil pressure continues to decrease, the brake auto-apply feature will activate and the ser- vice brakes will apply automatically to stop the truck. b. If the front tires do not steer, turn the key switch OFF and notify maintenance person- nel immediately. DO NOT drive the truck until the problem has been repaired and the truck can pass this test.
If the truck passes this test, the emergency steering system is functioning properly.