JLG 15/20MSP Service Manual - Manual (Page 148)

SECTION 6 - TROUBLESHOOTING
6-28 – JLG Lift – 3121231
Code 23 - Horn - Disconnected
Check For These Obvious Conditions First:
• Is machine equipped with a horn unit.
Code 24 - Auxiliary #1 Circuit - Short Circuit
Check For These Obvious Conditions First:
• Damaged wiring in the Auxiliary #1 Component wiring harness or a damaged Component.
Table 6-27. Code 23 - Horn - Disconnected
STEP ACTION SPEC YES NO
1. Is machine equipped with a horn unit. — Go to Step 3 Got to Step 2
2. At the Ground Control Module enter the programming mode, check if the
horn open circuit detection is enabled. — Disable It Replace Ground
Control Module
3. Check voltage at the P1 connector on the Ground Control Module between
pin-14 and pin-7. Is reading within specification? 2 - 4 V DC Replace Ground
Control Module
Go to Step 4
4. Remove the wire terminals at the horn, check continuity of each of the wires
from pins-14 and 7 on the P1 connector to the horn end. — Replace the
Horn
Repair or
Replace Wiring
Table 6-28. Code 24 - Auxiliary #1 Circuit - Short Circuit
STEP ACTION SPEC YES NO
1. At the Ground Control Module, P1 connector, check the voltage across
pins-9 and 2 to the horn. Is reading within specification? 0 - 2V DC Go to Step 2 Replace Ground
Control Module
2. Remove the wire terminals at the horn, check continuity of each of the wires
from pins-9 and 2 on the P1 connector to the component end. — Replace the
Component Repair or
Replace Wiring