JLG 20VP (3120849) Service Manual User Manual
Page 60

SECTION 3 - TROUBLESHOOTING
3-4
– JLG Lift –
3120849
Table 3-2. MC-1 ERROR CODES
(Indicated by rapid LED flashing and periodic beep)
ERROR
CODE
LED’S
FLASHING
PROBABLE CAUSE
REMEDY
0
8
System Overvoltage - Charger
Unplug Charger
0
8
System Overvoltage - Driving down long steep grade Operate ground controls to reduce voltage
1
7
Controller Overtemperature
Turn unit off and allow to cool
2
8
Drive Motor Plug - Open Circuit - check connectors
X103 & X104
Properly attach wires or pins A1 & A2
2
8
Drive Motor Plug - Open Circuit - check motor con-
nections at motor
Properly attach wires or pins (WHT & BLK wires)
3
6
Brake Safety Relay
Replace Controller
4
2
Brake Short Circuit
Replace Brake
5
2
Brake Left Open Circuit - D-connectors to X103 &
X104 switched
Switch D-connectors - Left Motor to X103; Right
Motor to X104
5
2
Brake Left Open Circuit - Check pins 3 & 5 of X103
and brake wires
Properly attach wires or pins
5
2
Brake Left Open Circuit - Check brake wires or plug at
drive motor
Properly attach wires or pins
6
2
Brake Right Open Circuit - Check pins 2 & 5 of X104
and brake wires
Properly attach wires or pins
6
2
Brake Right Open Circuit - Check brake wires or plug
at drive motor
Properly attach wires or pins
7
2
Brake Open Circuit on one or both brakes
See above
8
9
Switch Short Circuit (Joystick)
Replace Joystick Box
9
6
Power Circuit Defect
Replace Controller
10
1
Battery Low (< 16.5 v)
Charge Battery
11
9
Check pins & wire connections at X102 & joystick
box connector
Properly attach wires or pins
11
9
Joystick defective
Replace Joystick Box
12
8
Check pins & wire connections at X102 & joystick
box connector
Properly attach wires or pins
12
8
Joystick Box
Replace Joystick Box
16
7
Current Limiting - Motor Short Circuit - Gearmotor
defective
Replace Gearmotor
21
6
36v supply
Replace controller
24
5
Configuration Lost
Reprogram using MC-1 software, if error reoccours
then replace controller
25
6
RAM ROM
Replace controller