Operation - Section 3 OM3037 Page 3-20 Operating Instructions OVERRIDE SWITCH Push the Retard Speed Control Switch knob “IN” to turn “OFF”. This push-button switch (9, Figure 3- 5) is spring-loaded to the “OFF” position. When pushed in and held, this switch may be used for several functions: 1. The override switch permits the operator to move the truck forward when the Selector Switch is in Forward, the dump body is raised, and the brakes are released. Pull the Retard Speed Control Switch knob “OUT” to turn the system “ON”. ! Use of the override switch for this purpose is intended for emergency situations only! 2.
If the operator stops the truck on an uphill incline, the override switch can be used to set up forward propulsion while the brakes are applied. As soon as forward propulsion is felt, completely release the brakes and as truck begins to move forward, release the override switch. 3. The push button deactivates the retard pedal function when speed of truck is below 3 mph (4.8 kph). 4. The override switch is also used to reset an elec- tric system fault when indicated by the red warn- ing light (Refer to “Instrument Panel And Indicator Lights”, Overhead Warning/Status panel ).
RETARD SPEED CONTROL (RSC) ADJUST DIAL The RSC Adjust Dial (12, Figure 3-5) allows the opera- tor to vary the downhill truck speed that the Retard Speed Control system will maintain when descending a grade. 10, Figure 3-5: BLANK When the dial is rotated counterclockwise toward this symbol, the truck will descend a grade at lower speeds. This position is not currently used. RETARD SPEED CONTROL (RSC) “OFF/ON” SWITCH When the dial is rotated clockwise to- ward this symbol, the truck speed will increase. The Retard Speed Control Switch (11, Figure 3-5) turns the system “OFF” or “ON”. Throttle pedal position will override RSC setting.
If the operator depresses the throttle pedal to increase truck speed, Dynamic Re- tarding will not come on unless truck overspeed setting is reached or foot operated retard pedal is used. When the throttle pedal is released and RSC switch is “On”, Dynamic Retarding will come on at, or above, the RSC dialed speed and will adjust truck speed to, and main- tain, the dialed speed.