Model 4700 Maintenance Manual
Section 8. Theory of Operation
Single Traction Motor Trucks >S/N 10676 Item
Connection
Function Description
Theory of Operation
Pinout Matrix Normal Level
Signal Source
Signal User
132
J34-7
GND
B– supply to the VM. This B– is shared by many components prior to and after the VM. If not present, follow back towards B– until loss can be determined.
Battery voltage wrt BT1+
B– at J1–
VM
133
J34-8
GND
B– supply to the VM. This B– is shared by many components prior to and after the VM. If not present, follow back towards B– until loss can be determined.
Battery voltage wrt BT1+
B– at J1–
VM
134
J34-9
HORN OUT
Output from the VM to activate the Horn (HR1 at J11-IN). If not present, check VM, horn push button, and wiring.
+24V; 0V activated
VM
HR1
135
J34-10
GND
B– supply to the VM. This B– is shared by many components prior to and after the VM. If not present, follow back towards B– until loss can be determined.
Battery voltage wrt BT1+
B– at J1–
VM
136
J34-11
+24V
+24V input to VM from DC/DC converter (J96-4). If not present, check converter, wiring and connections.
+24V
DC/DC Converter
VM
137
J34-12
+24V CAN
+24V output from the VM to Armrest +24V Board (J139-5) and Operator Display (J137-5). If not present, check VM, wiring, and connections.
VM
Armrest Board, OD
138
J34-13
BRAKE LIGHT
+24V output from VM to the Brake Lights (LP1 and LP3) when traveling and changing direction or traveling and pressing brake pedal. If not present, check VM, wiring, and connections.
+24V
VM
Brake Lights
139
J34-14
PARK
Input to the VM from Parking Brake switch (SW7 at J30-3). If not present, check switch, wiring, and connections.
Approx. 5V brake set; 0V brake released
SW7
VM
140
J34-15
BRAKE
Input to the VM from the Brake Pedal switch (SW6 at J31-2). If not present, check switch, wiring, and connections.
Approx. 5V pedal not depressed; approx. 0V pedal depressed
SW6
VM
141
J34-16
HORN IN
Input to VM from Horn switch (PB4 at J8-2). If not present, check horn switch, wiring, and connections.
Approx. 5V open; 0V switch closed
PB4
VM
142
J34-17
OIL BRAKE
Input to VM from Low Brake Fluid Sensor (SW3). If not present, check switch, wiring, and connections.
Approx. 5V open; 0V switch closed
SW3
VM
Publication 1160093, Issued: 20 May 2013
8-59
