Toro 41188, Service Manual

Page: 162 / 353

Multi Pro 1750
Page 5 − 60
Electrical System
Flow Meter Sensor
The flow meter measures the spray system flow as it
moves through the flow meter. The sensor is an input to
the Toro Electronic Controller (TEC). Accurate informa-
tion from the flow meter is necessary to calculate appli-
cation rate. The flow meter is located just upstream of
the section manifold assembly (Fig. 82). The sensor
uses a magnetically based, Hall Effect integrated circuit.
As the rotor in the flow meter turns, the sensor accurate-
ly senses the rotor movement. The relationship of the
sensor to the rotor is critical as the sensor is designed
to read movement in one direction and must be perpen-
dicular to the rotor. The sensor connector pin 2 is the
positive lead, the connector pin 1 is the ground lead and
the connector pin 3 is the signal output. For flow meter
service information, see the Spray System chapters in
this manual.
NOTE: If the flow meter sensor or body is being tested,
serviced or replaced, calibrate the flow meter after in-
stallation (see Calibrating the Sprayer Flow in the ma-
chine Operator’s Manual).
Testing
1. Park machine on a level surface, stop engine and en-
gage parking brake.
2. Disconnect machine wire harness from flow meter
sensor.
3. Test the machine wire harness to the flow meter sen-
sor:
A. Set the ignition switch to the RUN/PREHEAT po-
sition.
B. Set the spray−mode switch located on the instru-
ment panel to the MANUAL position.
C. Set the spray pump, master boom and Spray
Boom switches located on the control console to the
ON position.
D. Access the InfoCenter Display Total Area or Sub−
Area Screens (see Spray System Chapters in this
manual).
E. Connect a jumper wire across the ground (−) pin 1
and the signal (+) pin 3 (Fig. 83A). Watch the Info-
Center Display as you open and close the connec-
tion across the pins multiple times, the total volume
sprayed reading should increase.
F. Remove the jumper wire.
G. Use a multimeter set to DC voltage and check for
5 VDC across the supply (+) pin 2 and ground (−) pin
1 of the machine wire harness (Fig. 83B).
H. Turn the ignition switch to OFF.
1. Flow meter 2. Section manifold
assembly
Figure 82
1
2
1. Machine wire harness
connector
2. Jumper wire
3. Multimeter probe (typ.)
Figure 83
1
2
3
1
3
12 VDC
A
B
1 2
3
2
1
4. Test flow meter sensor:
A sensor test harness is required to quickly check sen-
sor operation without removing the sensor from the flow
meter.
NOTE: Instructions for fabricating and using a flow me-
ter sensor test harness can be found in the Special Tools
section of this chapter.