Service Manual

GLOSSARY
Demystification Glossary 3 - 11
Module, KeyChoice™ Reverse
Operating System (Manual PTO
Clutch)
Purpose
The Key Choice™ Reverse Operating System module
works with the KeyChoice™ switch, PTO switch, and
the reverse switch. It responds to the reverse switch; if
the override switch (KeyChoice™ switch) is not
activated and the PTO is engaged, it will stop the
engine (Figure 12).
Figure 12
mvc-692
How it Works
The Key Choice™ Reverse Operating System is made
up of several components, such as diodes and relays.
When it is connected in the circuit, voltage is applied to
certain terminals of the Key Choice™ Reverse
Operating System module from the PTO switch,
reverse switch, and the override switch, which
energizes certain relays in the module. If voltage is not
applied to the proper terminals on the Key Choice™
Reverse Operating System module, the engine will
stop.
Testing
The Key Choice™ Reverse Operating System module
must be removed from the circuit. Using a multimeter
check the following:
* NOTE: If multimeter does not have a diode scale,
this test can not be done. This is not a problem if
powered tests are done. Powered test must be done to
check out relays (Figure 13).
Figure 13
Powered circuit test (with module out of circuit). A
12 volt battery is needed for this test. NOTE: USE
CAUTION WHEN MEASURING RESISTANCE WITH
A POWERED CIRCUIT. CONTACTING A VOLTAGE
SOURCE WITH METER IN OHMS POSITION CAN
SERIOUSLY DAMAGE THE METER.
**NOTE: Actual reading should be same as B+
applied to Pin 2.
Meter
Scale
Meter
Probe
Negative
Meter
Probe
Positive
Meter Reading
Ohms Pin 3 Pin 1 Open (more than
100k ohm)
Ohms Pin 3 Pin 2 350 to 450 ohms
Diode Pin 3 Pin 4 0.7V to 1.0V *
Diode Pin 3 Pin 5 0.7V to 1.0V *
Ohms Pin 3 Pin 6 Open (more than
100k ohms)
Ground
B+
(12V)
Meter
Probe
Neg.
Meter
Probe
Pos.
Meter
Scale
Meter
Reading
Pin 3 Pin 4 Pin 3 Pin 1 Ohms <2 ohms
Pin 3 Pin 5 Pin 3 Pin 1 Ohms <2 ohms
Pin 3 Pin 2 Pin 3 Pin 1 Ohms <2 ohms
Pin 3Pin 2Pin 3Pin 6Volts12 V **
Glossary