E70B EXCAVATOR MONITORING SYSTEM Caterpillar

Troubleshooting of Electronic Monitoring System (EMS)

Usage:

Take following test procedures for any problems, except those occur in meters.

Problems in meters should be corrected by directly proceeding to individual troubleshooting sequence charts.

Sequence Chart of Troubleshooting

When a voltage is to be checked during the test procedures, a voltage in excess of 24V must be available, if the state of "a voltage being available" is to be created. All voltages less than 24V are regarded as the state of "no voltage being available".

Failure of an electric component results from failure of other components or can cause failure of other components. Before a faulty electric component is replaced, be sure to locate the cause of the failure.

How to Read Troubleshooting Sequence Charts

Index number (No.) in Sequence charts shows where to find "Investigation procedures for check item & Probable cause" complied in later pages.

Proceed the troubleshooting step by step following the sequence chart together with above investigation procedures.

Disassembling of Monitor panel and its Parts Exchange.

Perform it following "Parts exchange procedures for Monitor panel" complied in later pages.

Electric circuit Diagram (Shown EMS related circuit only)

Wiring Identification

The colors and sizes of wires shown in the ELECTRIC CIRCUIT DIAGRAM are identified as described below.

Pin Configuration in Connector

Test I

Problems

Problem 1

Problem 2

When any of the following lamps fails to light, refer to above sequence chart.

Problem 3

Problem 4

Problem 5

Problem 6

Test II

Problems

Problem 7

Problem 8

Problem 9

Problem 10

Problem 11

Problem 12

Problem 13

Problem 14

Problem 15

Problem 16

Test III

Problems

Problem 17

Problem 18

Problem 19

Problem 20

Check following problems.

Fan belt loose

Coolant insufficient

Radiator core clogged

Coolant hose damaged

Check to ensure that the engine is cool enough and that the lamp is OFF. If the lamp does not go out, re-perform PROBLEM 11 of TEST II.

Problem 21

Problem 22

Replace the hour meter.

Problem 23

Problem 24

Problem 25

Problem 26

Problem 27

Test IV

Problems

Problem 28

Measuring Instrument

8S4627 Circuit (Continuity) Tester

To perform a continuity test (check), use either a circuit tester (8S4627) or Caterpillar digital multitester (6V3030).

5P7277 Voltage Tester

To perform a voltage test (check), use either a voltage tester (5P7277) or Caterpillar digital multitester (6V3030).

Digital Multitester (6V3030)

To measure voltage or resistance, use a Caterpillar digital multitester (6V3030).

Investigation Procedures for Check Item and Problem Cause

(Hyd #1) Voltage Test of Battery

The lights should be ON when this measurement is performed.

(Hyd #2) Fuse Box and Fuse

(Hyd #3) Checking Fuse (If the fuse is good)

(Hyd #4) Checking Fuse of Monitor Panel

1. Set the starting switch to "ON" and then to "OFF" and check the condition of the fuse.

2. Reconnect the harness connector (CONN3F) to the monitor panel and set the starting switch to "ON".

(Hyd #5) (CONN3F) Checking Voltage at Harness Connector of Monitor Panel

Ground the clip of the tester to the machine body (electric ground) and touch the point of the tester to socket (No.).

(Hyd #6) Checking Voltage at Harness Connector of Monitor Panel

Check sockets (10) and (8) of the harness connector (CONN3F) and sockets (10) and (9).

(Hyd #7) LAMP BUZZER Switch Continuity Test

(Hyd #8) Lamp Bulb Continuity Test

(Hyd #9) Voltage Test at Harness Connector CONN57 to Alarmer

1. Turn on the starting switch.

2. Turn on the lamp and buzzer switch.

(Hyd #10) Hour Meter Activation

(Hyd #11) Continuity Test between Harness Connectors CONN3F and CONN18F

(Hyd #12) Continuity Test between Harness Connector CONN18(1) and Body Ground

(Hyd #13) Measurement of Safety Relay Resistance

(Hyd #14) Voltage Check at (1) of CONN36F

(Hyd #15) Operational Check on Lamp and Buzzer Switch

(Hyd #16) Connection of Wire to Body Ground

1. With the starting switch "ON", disconnect the wire from the thermoswitch and connect it to the body ground.

(Hyd #17) Continuity Test of Harness Connector on Monitor Panel

1. Make a continuity test between CONN3F·(No.) and body ground.

(Hyd #18) Continuity Test between Thermoswitch and Body Ground

(Hyd #19) Monitor Panel Continuity Test

(Hyd #20) Connection between CONN1F·(6) and Body Ground

1. Connect CONN1F·(6) for the power unit controller to the body ground.

2. Turn on the starting switch and check if the lamp goes out.

(Hyd #21) Continuity Test between CONN1F and CONN3F

1. With CONN1F· (6) connected to the body ground, disconnect CONN3F from the monitor panel.

(Hyd #22) Connection of Fuel Tank Unit Wire to Body Ground

1. Turn off the starting switch.

2. Detach the wire (yellow/black) connected to the fuel tank unit, and connect it to the body ground.

3. Check if the fuel gauge pointer deflects beyond the maximum when the starting switch is turned on.

(Hyd #23) Connection between Wire (yellow/black) and wire (black)

1. With the starting switch turned on, connect the wire (yellow/black) and wire (black) for the fuel tank unit with each other, and check if the fuel gauge pointer deflects beyond the maximum.

(Hyd #24) Continuity Test between Wire (black) to Fuel Tank Unit and Body Ground

(Hyd #25) Meter Board Voltage Test

1. Connect the harness connector to the monitor panel.

2. Make sure that there is no contact between the board and other conductors, and turn on the starting switch.

3. Check the voltage of the meter securing bolts. Check all the nuts for looseness at the same time. This check is made by attaching one probe of the tester to (A) to (I) and the other probe to the body ground.

(Hyd #26) Check of Fuel Gauge on Meter Board

1. Connect fuel gauge securing bolt (I) to the body ground through a jumper wire, and check if the meter pointer deflects beyond the maximum.

(Hyd #27) Disconnection of Wire from Fuel Tank Unit

1. Disconnect the wire (yellow/black) from the fuel tank unit, and check if the fuel gauge pointer deflects beyond the green zone when the starting switch is turned on.

(Hyd #28) Continuity Test between Monitor Board and Meter Board

1. Make continuity checks between CONN3M· (No.) and the gauge securing bolts (A) to (I) Check the securing nuts for looseness at the same time.

(Hyd #29) Monitor Panel Continuity Test

(Hyd #30) Belt Tension Test

1. Make sure that the belt will have the slack of about 12 mm when the middle of the belt is forcibly pushed by a thumb.

(Hyd #31) Adjustment of Alternator Belt Tension

1. Loosen the upper and lower alternator fixing bolts (arrows). Make adjustments by moving the alternator with the handle of a wrench, etc., inserted.

(Hyd #32) Voltage Measurement at Alternator CONN37

1. Attach one probe of the tester to the E terminal, and the other probe to the P terminal. The engine is in operation now. Be careful in measuring.

(Hyd #33) Voltage Measurement at Safety Relay CONN18·(3)

1. Attache the one probe of the tester to the body ground, and the other probe to the harness connector CONN18F·(3).

(Hyd #34) Charge Lamp Check

(Hyd #35) Connection of Engine Oil Pressure Switch Wiring to Body Ground

(Hyd #36) Continuity Test to Body Ground

1. Check the continuity between the ground wiring (black) from the engine oil pressure switch and the body ground.

(Hyd #37) Voltage Check at Harness Connector CONN3F

(Hyd #38) Voltage Check at Hour Meter Connector

1. Attach the one probe of the tester to the wired (black) connector and the other probe to the wired (red) connector.

(Hyd #39) Continuity Test between CONN3F· (4) and CONN18F·(5)

(Hyd #40) Continuity Test between CONN18F·(5) and Body Ground

(Hyd #41) Connection of Coolant Temperature Gauge Unit Wiring to Body Ground

1. Check if the pointer of the coolant temperature gauge deflects beyond the maximum.

2. Make a check on each component of the thermo-unit by measuring its resistance at the specified temperature according to the thermo-unit characteristic table.

(Hyd #42) Check of Coolant Temperature Gauge on Meter Board

(Hyd #43) Check of Coolant Temperature Gauge

(Hyd #44) Connection of Hydraulic Oil Temperature Gauge Unit Wiring to Body Ground

1. Check if the pointer of the hydraulic oil temperature gauge deflects beyond the maximum.

2. Make a check on each component of the thermo-unit by measuring its resistance at the specified temperature according to the thermo-unit characteristic table.