5 troubleshooting section - table of contents, Ohm ratings for various components 3-16, Main power circuit troubleshooting – JLG 20VP (3120728) Service Manual User Manual
Page 75: Unit will not power up from ground control 3-17, No power at platform control 3-18, Drive train troubleshooting, Won’t drive (platform lowered or elevated) 3-20, Won’t drive (platform elevated only) 3-22, Won’t climb grade 3-24, Drives in opposite direction 3-25
SECTION 3 - TROUBLESHOOTING
3120728
– JLG Lift –
3-15
3.5
TROUBLESHOOTING SECTION - TABLE OF CONTENTS
OHM RATINGS FOR VARIOUS COMPONENTS
PAGE
Ohm Ratings for Various Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
MAIN POWER CIRCUIT TROUBLESHOOTING
Unit Will Not Power Up From Ground Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
No Power At Platform Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
Won’t Drive (Platform Lowered Or Elevated) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20
Won’t Drive (Platform Elevated Only). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
Won’t Climb Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-24
Drives In Opposite Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-25
Will Only Drive A Short Distance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-26
Won’t Drive Straight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-28
Noise From Drive Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-29
Platform Will Not Lift Up Using Platform Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-30
Platform Will Not Lower Using Platform Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33
Platform Will Not Lift Up From Ground Control Toggle Switch . . . . . . . . . . . . . . . . . . . . . . . . . 3-34
Platform Will Not Lower From Ground Control Toggle Switch . . . . . . . . . . . . . . . . . . . . . . . . . 3-35
Platform Will Not Lower Manually . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-36
Platform Lift Up And Down Jerky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-37
Mast Noisy When Lifting And Lowering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-38
Platform (Mast) Won’t Stay Elevated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-39
Platform (Mast) Descends Too Slowly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40
HYDRAULIC LEAK TROUBLESHOOTING
Miscellaneous Hydraulic Leak Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-41
BASE FRAME COMPONENTS TROUBLESHOOTING
Caster Wheels Not Operating Freely . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-42
Pot Hole Protection (PHP) Bars Will Not Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-42