6-40

GROUP 4 MECHATRONICS SYSTEM

CN-75

2

1

EPPR VALVE

8

CN-50

24

28

CN-47

1

2

1

2

CN-19

36

2

1

CN-19BCONTROLLER

FUSE

NO.11

RESISTOR

Wiring diagram

1. ALL ACTUATORS SPEED ARE SLOWBoom, Arm, Bucket, Swing and travel speed are slow, but engine speed is good.Spec : M-mode 1850 50rpm H -mode 1850 50rpm S-mode 1750 50rpmBefore carrying out below procedure, check all the related connectors are properly inserted.

IINSPECTION PROCEDURE

11)

SPEC : 200~450mASee TEST 2

SPEC : 5~20kgf/cm2See TEST 3

SPEC : 17.51(20C)See TEST 1

Check if EEr : 03on the cluster

Check electric current at EPPRvalve

Check resistance at EPPR valve

Check pressure at EPPR valve

YES

YES

YES

YES

NO

NO

NONO

Cause Remedy

Defectivehydraulic system

DefectiveEPPR valve

Defective CPUcontroller

Short circuit orpoor connectionbetween CN-50 -CN-75

Defective EPPRvalve

Replace

Replace

Check & repairwire harness orbetween CN-50-CN-75

Replace

2907A6MS01

6-41

Test 1 : Check resistance at connectorCN-75.

Starting key OFF.Disconnect connector CN-75 from EPPRvalve at main hydraulic pump.Check resistance between 2 lines asfigure.

(1)

TTest 2 : Check electric current at EPPRvalve.

Install multimeter as figure.Start engine.Set the accel dial at "10"(MAX)Set S-mode and cancel auto decel mode.If tachometer show approx 175050rpmcheck electriccurrent.

(2)

SPEC : 17.51(20C)

SPEC : 200~450mA(S mode)

6-38(2)

6-38(3)

SPEC : 5~20kgf/cm2(70~280psi)Test 3 : Check pressure at EPPR valve.Remove plug and connect pressuregauge as figure.Gauge capacity : 0 to 40~50kgf/cm2

(0 to 570~710psi)Start engine.Set the accel dial at "10"(Max).Set S-mode and cancel auto decel mode.If tachometer show approx 175050rpmcheck pressure.If pressure is not correct, adjust it.After adjust, test the machine.

((3)

6-39(1)

6-42

Wiring diagram

CN-75

2

1

EPPR VALVE

8

CN-50

24

28

CN-47

1

2

1

2

CN-19

36

2

1

CN-19BCONTROLLER

FUSE

NO.11

RESISTOR

2. ENGINE STALLBefore carrying out below procedure, check all the related connectors are properly inserted.INSPECTION PROCEDURE1)

YES

SPEC : 200~450mASee TEST 4

SPEC:5~20kgf/cm2See TEST 5

SPEC : 17.51(20C)See TEST 1

Check electriccurrent at EPPRvalve

Check pressureat EPPR Valve

Check resistancebetween CN-50(8) - (36)

Cause Remedy

Not enough enginepower

Defective EPPRvalve

Short circuit orpoor connectionbetweenCN-50 - CN-75

Defective EPPRvalve

Contact cumminsengine dealer

Replace

Check and repairwire harness

Replace

YES

YES

NO

NO

NO

2907A6MS01

6-43

TEST PROCEDURE

Test 4 : Check electric current at EPPRvalve at S-mode

Install multimeter as figure.Start engine.Set the accel dial at "10"(max)Set S-mode with 175050rpm.Check electric current.

CN-75

Multimeter

EPPR VALVE

CN-75

Supply line, pilot press

Pressure adjustingscrew locknut

(1)

22)

Test 5 : Check pressure at EPPR valve atS-mode

Connect pressure gauge at EPPR valve.Start engine.Set the accel dial at "10"(max)Set S-mode with 175050rpm.Operate bucket lever completely push orpull.Hold arm lever at the end of stroke.Check pressure at relief position.

(2)

SPEC : 200~450mA

SPEC : 5~20kgf/cm2(70~280psi)

6-44(1)

6-44(2)

6-44

3. MALFUNCTION OF CLUSTER OR MODE SELECTION SYSTEMBefore carrying out below procedure, check all the related connectors are properly inserted.INSPECTION PROCEDURE

11)

See if Co : Eron the cluster

See if all lampsoff in the CPUcontroller case

Check connectionbetween CN-51(29) - CN-50(10)or CN-50(30) -CN-5(11)

Cause Remedy

No power supply tothe CPU controller

CPU failure

Cluster failure

No connection

Check fuse

Replace

Replace

Check and repair

CLUSTERPOWER IG(24V)GNDRXTX 4

CN-56 CN-5

3

CN-50

CPU CONTROLLER

11

10

30

29

FUSE

NO.11(CPU)

28

24

RY G

RY G

RY G

KEY OFF

Wiring diagram

YES

YES

YES

NO

OK

NONO

NO

36076MS02

6-45

4. AUTO DECEL SYSTEM DOES NOT WORKBefore carrying out below procedure, check all the related connectors are properly inserted.INSPECTION PROCEDURE

11)

Wiring diagram

Cause Remedy

Defective CPUcontroller

Short circuit orpoor connectionvetween CN-51(1),(13)- pressureswitches

Defective autodecel pressureswitch

Replace

Replace or repair

Replace

CPU CONTROLLER

CN-51

1Pb

Pa

AUTO DECEL PRESSURE SWITCH

CD-7

CD-6

1

2

1

2

13

SPEC :Actuator operating :

11~13VActuator stop :0~2V

See TEST 6See TEST 7

Check resistancebetween CN-51(1)-GND andCN-51(13)-GND

NO

NO

YES

R29076MS10

6-46

TEST PROCEDURE

Test 6 : Check voltage at CN-51(1) andground.

Prepare 1 piece of thin sharp pin, steel orcopper.Starting key ON.Insert prepared pin to rear side ofconnectors : One pin to (1) of CN-51.Check voltage as figure.

Test 7 : Check voltage at CN-51(13)andground.

Prepare 1 piece of thin sharp pin, steel orcopperStarting key ON.Insert prepared pin to rear side ofconnectors : One pin to (13) of CN-51Check voltage as figure.

CN-50

Y R G

Multimeter

CN-51 1122536

24

CPUCONTROLLER

CN-51

PIN

Ground

Multimeter

CN-51 1122536

1324

Ground

(1)

(2)

22) SPEC : Actuator stop : 11~13VActuator operating : 0~2V

R29076MS11

6-47

48

CN-50

25

CONTROLLER

27

26

CN-3

5

7

6

ECM

37

47

CN-174

RESISTORABC

A

BCN-99

RESISTORABC

A

B

Wiring diagram

SPEC : Below 10KEY OFF

SPEC : Below10KEY OFFCheck resistance

between CN -51(25) - ECM(48)

Check resistancebetween CN-50(26) - ECM(47)

Defective cluster orCPU controller orECM

Poor connectionbetween CN-51(26) - ECM(47)

Poor connectionbetween CN-51(25) - ECM(48)

Repair or Replace

Repair

Repair

55. MALFUNCTION OF WARMING UPBefore carrying out below procedure, check all the related connectors are properly inserted.INSPECTION PROCEDURE

1)

Cause Remedy

YES

YES

NO

NO

2907A6ES02

6-48

Wiring diagram

SPECKEY ON : 241VKEY OFF : 0VSee TEST 8

SPEC: 15-30See TEST 8

Is voltage betweenCN-88(2) -GNDnormal?

Resistancebetween CN-51(2)-GND normal?

Check resistancebetween CN-88(1) - (2)

Defective powermax. solenoid valve

Short circuit or poorconnectionbetween CN-51(2) -CS-29 and CN-50(3) -CN-88(1)

Short circuit or poorconnectionbetween CN-88(2)-battery relay(+)

Repair or replace

Repair or replace

Repair or replace

66. MALFUNCTION OF POWER MAXBefore carrying out below procedure, check all the related connectors are properly inserted.INSPECTION PROCEDURE1)

POWER MAX SOLENOID

CS-29

3

CN-50

CPU CONTROLLER

2

CN-51

POWER MAX SWITCH

2

1

CN-88

2

CN-4

FUSE

NO.25

2

1

1

Cause RemedyYES

YES

NO

NO

50076MS04

SPEC : Power max button pressed ON : 0Power max button released OFF : See Test 9

6-49

TEST PROCEDURE

Test 8: Check voltage between connectorCN-88 - GND.

Start key ON.Disconnect connector CN-88 from powermax solenoid valve.Check voltage as figure.

(1)

22)

Test 9 : Check resistance betweenconnector CN-51(2)-GND.

Starting key OFF.Remove CPU controller and disconnectconnector CN-51 from CPU controller.Check resistance as figure.

(2)

LH RCV-lever

Power max. switch

Power max.solenoid valve

CN-88

Multimeter

CN-88

CN-50

Y R G

CPUCONTROLLER

CN-51

Multimeter

CN-51212

2536

1324

Ground

SPEC : Key ON : 241VKey OFF : 0VResistance : 15~30

SPEC : Power max button pressed ON : 0Power max button released OFF :

R29076MS14

R29076MS15