TCM FB-8 Series, Service Manual

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2. ELECTRICAL PARTS AND PROCEDURES FOR CHECKING
2.2.11 STEERING POTENTIOMETER
The steering potentiometer is used to detect the
turning angle of the left rear wheel. It is located on
the top of the left-side king pin on the rear axle.
The motor speed is controlled according to the
angle at which the left rear wheel to prevent it from
exceeding the preset value.
1. Checking procedure
With the truck in the maintenance mode (See
2.2.20.), check the voltage at point D.
When the left rear wheel is in the straight-ahead
•
position: 2.4 to 2.7 V
When the left rear wheel is turned all the way left: about 3.6 V
•
When the left rear wheel is turned all the way right: about 1.9 V
•
Whenever the steering potentiometer or the drive motor inverter unit is replaced with a new one,
•
it will be necessary to set the center, right-end and left-end positions of the steering wheel into the
steering potentiometer in the following manner:
2. Operating procedure
■
Using the steering memory switch
(1) With the key switch turned off, connect
a steering memory switch (part number:
280B2-60991) to the 3P coupler near the
center of the floorboard (on the side where
the truck-body harness is found).
(2) Press the steering memory switch while
turning the key switch on. Then, release the
steering memory switch to turn it off to put
the steering potentiometer in the read-in
mode. The buzzer will sound for 1 second.
(3) Turn the steering wheel counterclockwise
all the way and then press and release the
steering memory switch. The buzzer will
sound for 1 second. (The full left position will
have been stored in memory.)
(4) Return the steering wheel to the center. Then press and release the steering memory switch. The
buzzer will sound for 1 second. (The center position will have been stored in memory.)
(5) Turn the steering wheel clockwise all the way. Then press and release the steering memory switch.
The buzzer will sound for 1 second. (The full right position will have been stored in memory.)
(6) Return the steering wheel to the center and turn the key switch off.
(7) Remove the steering memory switch.
Steering memory switch