Bendix Commercial Vehicle Systems ET-2 ELECTRONIC THROTTLE 6/04 - Manual (Page 2)

2
FIGURE 4 - EXPLODED VIEW
Figure 3 illustrates the relationship between throttle position
and engine RPM. Potentiometer performance will vary for
each engine application, therefore potentiometers must not
be interchanged.
WARNING! PLEASE READ AND FOLLOW
THESE INSTRUCTIONS TO
AVOID
PERSONAL INJURY OR DEATH:
When working on or around a vehicle, the following
general precautions should be observed at all times.
1. Park the vehicle on a level surface, apply the
parking brakes, and always block the wheels.
Always wear safety glasses.
2. Stop the engine and remove ignition key when
working under or around the vehicle. When
working in the engine compartment, the engine
should be shut off and the ignition key should be
removed. Where circumstances require that the
engine be in operation, EXTREME CAUTION should
be used to prevent personal injury resulting from
contact with moving, rotating, leaking, heated or
electrically charged components.
3. Do not attempt to install, remove, disassemble or
assemble a component until you have read and
thoroughly understand the recommended
procedures. Use only the proper tools and observe
all precautions pertaining to use of those tools.
4. If the work is being performed on the vehicle’s air
brake system, or any auxiliary pressurized air
systems, make certain to drain the air pressure from
all reservoirs before beginning ANY work on the
vehicle. If the vehicle is equipped with an AD-IS
™
air dryer system or a dryer reservoir module, be
sure to drain the purge reservoir.
5. Following the vehicle manufacturer’s
recommended procedures, deactivate the electrical
system in a manner that safely removes all
electrical power from the vehicle.
6. Never exceed manufacturer’s recommended
pressures.
7. Never connect or disconnect a hose or line
containing pressure; it may whip. Never remove a
component or plug unless you are certain all
system pressure has been depleted.
8. Use only genuine Bendix ® replacement parts,
components and kits. Replacement hardware,
tubing, hose, fittings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifically for such applications and
systems.
9. Components with stripped threads or damaged
parts should be replaced rather than repaired. Do
not attempt repairs requiring machining or welding
unless specifically stated and approved by the
vehicle and component manufacturer.
10. Prior to returning the vehicle to service, make
certain all components and systems are restored
to their proper operating condition.
PREVENTIVE MAINTENANCE
GENERAL
Perform the following tests and inspections at the prescribed
intervals. If the ET-2
™ treadle does not function as described,
repair it or replace it with a new unit, available at any
authorized Bendix parts outlet. EVERY 3 MONTHS, 25,000
MILES, OR 900 OPERATING HOURS:
1. Remove any accumulated contaminants and visually
inspect the exterior of the ET-2 ™ treadle for physical
damage or excessive corrosion.
2. Inspect electrical connections and cable assembly for
signs of corrosion, wear, or physical damage. Replace
as necessary.
3. Inspect springs (11, 12, 13) for signs of corrosion or
pitting. Replace as necessary.
4. Inspect bearings (10), washer (7), and snap rings (8)
for cracks or deterioration. Replace as necessary.
OPERATIONAL TEST
Perform these tests only if the vehicle’s throttle does not
appear to operate as expected.
Test 1: For Mack and DDC engines:
1. Unplug the cable assembly from the potentiometer’s
integral connector by lifting the lock tab and pulling
the connectors until they disengage. Inspect cable
assembly for loose terminals, frayed wires, corrosion,