TM 5-2410-241-23-1
0008
ELECTRICAL SYSTEM CONTINUED
Push button Switch (Upshift)
0008
Push button Switch (Downshift)
0008
Limit Switch (Direction/Reverse)
0008
The upshift switch (Figure 8, Item 2), the downshift switch (Figure 8, Item 3), and the secondary reverse switch
(Figure 8, Item 4) are components of the tiller handle. The switches are inputs to the ECM.
The upshift switch informs the ECM that the operator wants the transmission to upshift one gear. The upshift switch
is a single-pole double-throw (SPDT) switch. The upshift switch has two input connections to the ECM. One
connector is for the Normally Closed (N/C) contacts and the other is for Normally Open (N/O) contacts. When the
operator presses the upshift switch, the N/C circuit is open and the N/O circuit is closed to ground. When the switch
is not activated, the N/C circuit is closed to ground and the N/O circuit is open.
The downshift switch informs the ECM that the operator wants the transmission to downshift one gear. The
downshift switch is a SPDT switch. The downshift switch has two input connections to the ECM. One connector is
for the N/C contacts and the other is for the N/O contacts. When the operator presses the downshift switch, the
N/C circuit is open and the N/O circuit is closed to ground. When the switch is not activated, the N/C circuit is
closed to ground and the N/O circuit is open.
N OT E
The status of the inputs (upshift and downshift) must be correct in order for the ECM to
perform the shifting at the correct time.
The direction switch informs the ECM that the operator wants the transmission to shift to the reverse direction. The
transmission direction control lever (Figure 8, Item 1) actuates the direction switch. The direction switch is a
backup to the position sensor for the transmission direction control lever, which normally tells the ECM when
reverse is requested. The ECM only responds to the status of the direction switch when a failure in the position
sensor for the transmission direction control lever is detected. The direction switch is a SPDT limit switch. The
direction switch has two input connections to the ECM. One connection is for the N/C contacts and the other is for
the N/O contacts. When the operator turns the transmission direction control lever to the REVERSE position, the
reverse N/C circuit is open. When the operator turns the transmission direction control lever to the REVERSE
position, the N/C is open and the reverse N/O circuit is closed to ground. When the transmission direction control
lever is NOT in the REVERSE position, the switch is not activated. When the switch is not activated, the reverse
N/C circuit is closed to ground and the reverse N/O circuit is open.
0008-13
