Service Manual

SECTION 6 - TROUBLESHOOTING
6-24 – JLG Lift – 3121231
Code 14 - Pump Motor - Disconnected
Check For These Obvious Conditions First:
• Check the Positive (+)/Negative (–) cables from the Ground Control Module to the Pump Motor studs for loose or cor-
roded connections.
Code 15 - Lift Down Valve - Disconnected
Check For These Obvious Conditions First:
• Inspect wire terminals on the lift down valve at the base of the lift cylinder for tight and secure connection.
Table 6-18. Code 14 - Pump Motor - Disconnected
STEP ACTION SPEC YES NO
1. Check resistance across the positive (+) and negative (–) studs on the
pump motor.
SeeTable 6-2 Replace Ground
Control Module
Repair or Replace
Pump Motor or
Motor Brushes
Table 6-19. Code 15 - Lift Down Valve - Disconnected
STEP ACTION SPEC YES NO
1. Check voltage at the P1 connector on the Ground Control Module between
pin-10 and pin-3. Is reading within spec?
2 - 4 V DC Replace Ground
Control Module
Go to Step 2
2. Check resistance between the terminals on the lift down valve, located at
the base of the lift cylinder. Is reading within spec?
6 Ohms Repair or Replace
Wiring Harness
from Ground
Control Module
Replace the
Lift Down Valve
Solenoid
3. With the terminals still removed from the lift down valve coil, check continu-
it y o f t he wi res fr om pi ns 10 an d 3 on th e P 1 co nn ec to r t o the li f t d ow n val ve .
.00 Ohms — Repair or Replace
Wiring