Mec 3072ES, Service And Parts Manual

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PROBLEM REMEDY/SOLUTION POSSIBLE CAUSE
"3072ES / 3772ES / 3772ES HD" Service & Parts Manual October 2008
Page 4-33
Drive
Steer
No Speed Selection
Limit s witch n ot f un ctio n i n g Check limit s witch located o n left r ea r of ba s e
Check limit s witch i n p u t with EZ-Cal (EZ-Cal ID# 2d5)
No High Speed S peed/To r q u e s electo r s witch i n ope r ative
Valve S V4 n ot f un ctio n i n g
EP2 poppet valve n ot f un ctio n i n g
Check fo r 12 volt s o n all te r mi n al s of S peed/To r q u e s witch i n Platfo r m
Co n t r ol s box with d r ive e n abled.
Check voltage a n d g r o un d to valve
check fo r fa u lty valve s pool
Check o r r eplace valve
No Mid Speed S V3 o r S V4 powe r ed a n d/o r s hifted
S peed/To r q u e s electo r s witch malf un ctio n
The s e valve s s ho u ld n ot have 12 volt s .
I n mid- s peed, check valve f un ctio n
S ho u ld n ot have powe r at te r mi n al s 1 & 3 of S peed/To r q u e s witch i n
Platfo r m Co n t r ol s box with d r ive e n abled
Check fo r 12 volt s o n te r mi n al s 2 & 3 of S peed/To r q u e s witch i n platfo r m
co n t r ol box with d r ive e n abled.
Check fo r 12 volt s to valve
Check g r o un d to valve
Check fo r fa u lty valve s pool
Check o r r eplace vavle.
S peed/To r q u e s witch i n ope r ative
Valve S V3 n ot f un ctio n i n g
EP1 poppet valve n ot f un ctio n i n g
No low speed
(high torque mode)
No steer in either
direction Joy s tick r ocke r s witch i n ope r ative
S tee r i n g valve i n ope r ative
S y s tem I n te rru ptio n
Ho s e s co nn ected i n co rr ectly
P r e ssur e r elief valve s et too low
Check r ocke r s witch o u tp u t;
OUTPUT - g r ee n a n d yellow wi r e s .
INPUT - bl u e wi r e
Check s tee r i n g valve fo r powe r o r damage.
Check HELP a n d MODE me ss age o n EZ-Cal
S ee hyd r a u lic s ectio n fo r p r ope r co nn ectio n .
S et s tee r r elief valve to 2000 p. s .i.
Steers in one
direction only S tee r i n g valve i n ope r ative o r s t u ck
No powe r to s tee r i n g coil
S y s tem I n te ru ptio n
I ns pect – r eplace s tee r i n g valve
Check fo r powe r a n d g r o un g i n both di r ectio ns .
Repai r wi r i n g
Check HELP a n d MODE me ss age o n EZ-Cal
Steers, but not fully,
or steers slowly O n e o r both s tee r i n g cyli n de r / s i n te rn al s eal
fail ur e
P r e ssur e r elief valve s et too low
Ki n g pi n / s s eizi n g i n the bo r e
Check s tee r i n g cyli n de r s eal s – r eplace
S et s tee r r elief valve to 2000 p. s .i.
Di s a ss emble a n d i ns pect
Repai r
Replace b us hi n g s
continued…
TROUBLE Table continued