Operation and maintenance manual

Section 190-0270
Electrical System - Switches and Sensors
2
SM 2252 10-03
Tachometer/Hourmeter (9, Fig. 2) - Driven from the
alternator, the tachometer indicates the number of
engine crankshaft revolutions per minute (rev/min).
The needle shows the variations in engine operating
speed. Never accelerate the engine to speeds
indicated by the red zone on the dial face. A digital
hourmeter is incorporated in the tachometer to record
total hours of engine operation.
Tachometer Calibration
1. Determine the impulse setting required. Reference
tachometer calibration table.
1 - Engine Stop W/L
2 - Engine Check W/L
3 - Tractor Brakes Overstroke W/L
4 - Not Used On This Machine
5 - Not Used On This Machine
6 - Body Up W/L
14 - Headlight Main Beam Ind/L
15 - Retarder Apply Ind/L
16 - Brake Cooling Oil Temperature W/L
17 - Emergency Steering W/L
18 - Alternator Charging W/L
19 - Direction Indicator Ind/L
20 - Transmission Oil Temperature Gauge
7 - Trailer Brakes Overstroke W/L
8 - Parking Brake Ind/L
9 - Tachometer/Hourmeter
10 - Fuel Gauge
11 - Speedometer/Odometer
12 - Transmission Stop W/L
13 - Differential Lock Ind/L
Fig. 2 - Layout View of Instruments and Indicator/Warning Lights
SM - 2685
2. Using a suitable screwdriver, depress and hold
calibration button at the rear of the tachometer and
turn the ignition keyswitch to position '1'. Release
button when PULSE is displayed.
3. After a few seconds, the digits will flash in
sequence. Depress the button until the desired
number is displayed the release the button for a few
seconds until the next digit flashes.
4. Repeat step 3 to obtain the desired impulses/
revolution. The tachometer is now calibrated.
Transmission
Refer to Section 120-0010, TRANSMISSION AND
MOUNTING, for detailed information on switches and
sensors fitted to the transmission.
Speedometer/Odometer (11, Fig. 2) - Driven by a
signal from the transmission ECU, the speedometer
indicates vehicle travel speed in kilometres per hour
Tachometer Calibration Table -
All units with standard tyres
Unit Engine Pulses/revolution
TA25 Cummins QSC 17.40
TA27 Cummins QSL 17.40
TA30 Cummins QSM 16.68
TA35 DD Series 60 18.66
TA40 DD Series 60 18.66
0
5
10
15
20
25
RPM x100
30
0
10
30
20
40
km/h
50
MPH
20
20
20
20
OIL
TEMP
TRANS
50
150
120
140
P
1 2
STOP
STOP
9
20
11
10
16
17
18
19
12
13
14
15
5
6
7
8
1
2
3
4