Hyundai HL930A Operation & Maintenance Manual page 132

9) MACHINE CONTROL UNIT (MCU)
LED
10) TRANSMISSION CONTROL UNIT (TCU)
77073CDS91
11) ENGINE CONTROL MODULE (ECM)
7707A3CD03
12) CONTROL UNIT (electro hydraulic & joystick steering, EHCU)
(1) This consists of electronic parts and controls all lamps and buzzers
on the cluster in accordance with signals transmitted from the
switches, the ECM, TCU, the engine and the hydraulic pressure
sensors.
(2) Three LED lamps on the MCU display as below.
LED lamp
*1
G is turned ON
*2
G and R are turned ON
*3
G and Y are turned ON
Three LED are turned OFF
*1 : Green
*2 : Red
*3 : Yellow
(1) The control unit is shifting to the required gears fully-automatically
giving consideration to the following criteria:
• Gear selector lever position
• Driving speed
• Load level
(1) The engine control module (ECM) is the control center of the en-
gine system.
(1) The control unit is the control center of the EH control lever and joy-
stick steering system.
3-74
Trouble
Normal
Trouble on MCU
Trouble on serial communi-
cation line
Trouble on MCU power
Service
-
• Change the MCU
• Check if the serial commu-
nication lines between the
controller and the cluster
are disconnected
• Check if the input power
wire (24 V, GND) of control-
ler is disconnected
• Check the fuse