Allison Transmission 3000

b. Throttle Position Sensor (TPS) Adjustment—Using Diagnostic Tool. When
properly installed by the equipment manufacturer, the TPS should not need
adjustment. If TPS adjustment is necessary, confirm that it has been installed to
Allison Transmission specification (refer to Figure 5–5). The TPS is
self-calibrating and therefore has no optimum closed throttle or full throttle count
value. Idle count should be 50 or higher and full throttle count 200 or lower. As
long as the counts are in the 50 and 200 count range with a difference of 85 to
130 counts between closed and full throttle the TPS is set correctly.
Error codes occur if the idle position is less than 14 counts or when the full
throttle position is more than 233 counts.
The Allison DOC™ For PC–Service Tool can read TPS counts. Watch the TPS
movements as the controls move it through a full stroke. Be sure the following
conditions DO NOT EXIST:
• Misalignment or obstruction to smooth movement through the full stroke
• Idle and full throttle positions are not within an error zone (refer to
Figure 5–5)
c. Hitch-Pin Throttle Position Sensor Installation.
• Install the throttle sensor body as follows:
1. Clamp cable end using clamp and shims (refer to Figure 5–6).
0 COUNT
14 COUNTS
50 COUNTS
CLOSED
THROTTLE
WIDE OPEN
THROTTLE
233 COUNTS
255 COUNTS
200 COUNTS
APPROX.
19 mm (0.75 in.) STROKE
FULLY
EXTENDED
ERROR
ZONE
ERROR
ZONE
FULLY
RETRACTED
(AT REST)
Total Stroke
CT–WOT
15.2 mm–22.9 mm
(0.6 in.–0.9 in.)
85–130 Counts
Adjust so total stroke is within
50–200 count band
0 mm
2.5 mm
(0.1 in.)
40.6 mm
(1.6 in.)
45.7 mm
(1.8 in.)
V00429.05
Figure 5–5. Throttle Position Determination Diagram
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