Page 239 of 436
TEST TC-74AREPAIRING - REDUNDANT EMERGENCY STOP PLAUSIBILITY IN AFTER-RUN
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
TURN IGNITION ON,
ENGINE OFF. USING
THE DRB READ ECM
CODES.
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Page 243 of 436
TEST TC-75AREPAIRING - REDUNDANT EMERGENCY STOP POWERSTAGE DEFECTIVE
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
START TEST WITH THE DRB,
TC-75A. ERASE CODES.
CYCLE THE IGNITION DOES THE DRB
ON AND OFF SEVERAL WITH THE IGNITION DISPLAY "REDUNDANT YES CONTINUE TEST
TIMES, PAUSING FOR ON ENGINE OFF, EMERG STOP TC-75A ON THE
TEN SECONDS AT KEY READ CODES. POWERSTAGE NEXT PAGE.
ON AND OFF. DEFECTIVE"?
NO
AT THIS TIME THE REVIEW THE CIRCUIT
CONDITION FOR DESCRIPTION FOR A WERE ANY PROBLEMS YES REPAIR AS
SETTING THE CODE PROPER UNDERSTANDING FOUND? NECESSARY.*
IS NOT PRESENT. OF THIS CODE. CHECK
FIG.1 FOR PROBLEMS.
NO
REFER TO GENERAL
INFORMATION 3.3.2 YES
FOR ADDITIONAL TEST COMPLETE.*
INFORMATION ON
INTERMITTENT CODES.
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Page 249 of 436
TEST TC-79AREPAIRING - SOLENOID VALVE CONTROLLER OPEN CIRCUIT
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
KEY ON, READ CODES.
START TEST TURN IGNITION OFF. DOES THE DRB DISPLAY YES CONTINUE TEST
TC-79A. WITH THE DRB, "SOLENOID VALVE TC-79A ON THE
ERASE CODES. CONTROLLER OPEN NEXT PAGE.
CIRCUIT"?
NO
USE THE SCHEMATIC AS DOES THE DRB REPAIR THE HARNESS
A GUIDE AND WIGGLE MONITOR THE DRB DISPLAY "SOLENOID YES OR CONNECTOR THAT
THE SOLENOID VALVE DISPLAY. VALVE CONTROLLER CAUSED THE CODE TO
CONNECTOR & HARNESS. OPEN CIRCUIT"? SET.*
FIG.1
NO
AT THIS TIME, THE USING THE
CONDITION REQUIRED SCHEMATIC AS A WERE ANY PROBLEMS YES REPAIR AS
TO SET THE CODE IS GUIDE, INSPECT THE FOUND? NECESSARY.*
NOT PRESENT. WIRING AND
FIG.2 CONNECTORS.
NO
REFER TO GENERAL
INFORMATION 3.3.2 YES
FOR ADDITIONAL TEST COMPLETE.*
INFORMATION ON
INTERMITTENT CODES.
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Page 251 of 436

TEST TC-79ACONTINUED - REPAIRING - SOLENOID VALVE CONTROLLER OPEN CIRCUIT
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
TEST TC-79A KEY OFF.
CONTINUED FROM DISCONNECT THE
THE PREVIOUS FUEL PUMP ASSEMBLY
PAGE. HARNESS
CONNECTOR.**
KEY ON. MEASURE FUEL
USE A VOLTMETER IN PUMP HARNESS IS THE VOLTAGE YES REPAIR THE OPEN
THE FOLLOWING CONNECTOR CAVITY 10. BELOW 10.5 VOLTS? DIESEL POWER RELAY
STEP.OUTPUT CIRCUIT*
FIG.1
NO
TURN IGNITION OFF. USING AN OHMMETER, REPAIR THE FUEL
DISCONNECT THE ECM MEASURE THE FUEL IS THE RESISTANCE YES TIMING SOLENOID
HARNESS TIMING SOLENOID BELOW 5.0 OHMS? CONTROL CIRCUIT
CONNECTORS.** CONTROL CIRCUIT TO FOR A SHORT TO
GROUND. FIG.1 GROUND.*
NO
MEASURE THE FUEL REPAIR THE OPEN
USE AN OHMMETER IN TIMING SOLENOID IS THE RESISTANCE YES FUEL TIMING
THE FOLLOWING CONTROL CKT BETWEEN ABOVE 5.0 OHMS? SOLENOID CONTROL
STEPS. THE ECM AND THE FUEL CIRCUIT.*
PUMP ASSEMBLY. FIG.2
NO
MEASURE THE PUMP CONNECTOR (PUMP
RESISTANCE OF THE SIDE) BETWEEN IS THE RESISTANCE NO REPLACE THE FUEL
FUEL TIMING CAVITIES 5 AND 10. BETWEEN 12.0 AND INJECTION PUMP
SOLENOID AT THE 20.0 OHMS? ASSEMBLY.*
INJECTION... FIG.3
YES
NOTE: BEFORE
REPLACING THE ECM, DID THE FUEL YES REPLACE THE ENGINE
PERFORM TEST NTC-3A INJECTION PUMP CONTROL MODULE.*
TO CHECK INTERNAL PASS TEST NTC-3A?
FUEL PUMP CIRCUITRY.
NO
REPLACE THE FUEL
INJECTION PUMP
ASSEMBLY.*
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Page 253 of 436
TEST TC-80AREPAIRING - SOLENOID VALVE CONTROLLER SHORT CIRCUIT
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
KEY ON, READ CODES.
START TEST WITH THE DRB, DOES THE DRB DISPLAY YES CONTINUE TEST
TC-80A. ERASE CODES. TURN "SOLENOID VALVE TC-80A ON THE
IGNITION OFF. CONTROLLER SHORT NEXT PAGE.
CIRCUIT"?
NO
USE THE SCHEMATIC AS DOES THE DRB REPAIR THE HARNESS
A GUIDE AND WIGGLE MONITOR THE DRB DISPLAY "SOLENOID YES OR CONNECTOR THAT
THE SOLENOID VALVE DISPLAY. VALVE CONTROLLER CAUSED THE CODE TO
CONNECTOR & HARNESS. SHORT CIRCUIT"? SET.*
FIG.1
NO
AT THIS TIME, THE USING THE
CONDITION REQUIRED SCHEMATIC AS A WERE ANY PROBLEMS YES REPAIR AS
TO SET THE CODE IS GUIDE, INSPECT THE FOUND? NECESSARY.*
NOT PRESENT. WIRING AND
FIG.2 CONNECTORS.
NO
REFER TO GENERAL
INFORMATION 3.3.2 YES
FOR ADDITIONAL TEST COMPLETE.*
INFORMATION ON
INTERMITTENT CODES.
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Page 265 of 436
TEST TC-84AREPAIRING - TERMINAL 15 PLAUSIBILITY AFTER START-UP
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
START TEST WITH THE DRB,
TC-84A. ERASE CODES.
CYCLE THE IGNITION
ON AND OFF SEVERAL WITH THE IGNITION DOES THE DRB YES CONTINUE TEST
TIMES, PAUSING FOR ON ENGINE OFF, DISPLAY "TERMINAL TC-84A ON THE
TEN SECONDS AT KEY READ CODES. 15 PLAUSIBILITY"? NEXT PAGE.
ON AND OFF.
NO
AT THIS TIME THE REVIEW THE CIRCUIT
CONDITION FOR DESCRIPTION FOR A WERE ANY PROBLEMS YES REPAIR AS
SETTING THE CODE PROPER UNDERSTANDING FOUND? NECESSARY.*
IS NOT PRESENT. OF THIS CODE. CHECK
FIG. 1 FOR PROBLEMS.
NO
TEST COMPLETE.*
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Page 267 of 436

TEST TC-84ACONTINUED - REPAIRING - TERMINAL 15 PLAUSIBILITY AFTER START-UP
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
TEST TC-84A KEY OFF.
CONTINUED FROM DISCONNECT THE ECM
THE PREVIOUS HARNESS
PAGE. CONNECTORS.**
USING A VOLTMETER, NOTE: BE SURE TO IS THE VOLTAGE
MEASURE ALL ECM EXCLUDE CAVITIES ABOVE 2.0 VOLTS NO REPLACE THE ENGINE
HARNESS CONNECTOR 30,33,45 AND 51 FOR ANY OF THE CONTROL MODULE.*
CAVITIES EXCEPT FROM THIS STEP. MEASUREMENTS?
30,33,45 AND 51.
YES
IS VOLTAGE PRESENT REPAIR SHORT TO
AT ECM HARNESS NO VOLTAGE ON THE
CONNECTOR CAVITIES CIRCUIT THAT
2 OR 28? MEASURED ABOVE 2.0
VOLTS.*
YES
USING A VOLTMETER, REPAIR THE SHORT
REMOVE THE DIESEL MEASURE ECM HARNESS IS THE VOLTAGE YES TO VOLTAGE ON THE
POWER RELAY.** CONNECTOR CAVITY 2. ABOVE 2.0 VOLTS? DIESEL POWER RELAY
OUTPUT CKT.*
FIG.1
NO
TURN IGNITION OFF. THE DIESEL POWER REPAIR THE SHORT
USING AN OHMMETER, RELAY CONTROL CKT. IS THE RESISTANCE YES TO GROUND ON THE
MEASURE BETWEEN AT THE PDC. BELOW 5.0 OHMS? DIESEL POWER RELAY
GROUND AND... CONTROL CKT.*
FIG.2
NO
REPLACE THE DIESEL
POWER RELAY.*
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Page 273 of 436

TEST TC-86AREPAIRING - TIMING GOVERNING POSITIVE GOVERNOR DEVIATION
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
NOTE: INCORRECT HAS THE TIMING VERIFY CORRECT
START TEST INJECTION PUMP CHAIN, TIMING YES VALVE TIMING AND
TC-86A. TIMING CAN CAUSE GEARS OR INJECTION INJECTION PUMP
THIS TROUBLE CODE. PUMP BEEN SERVICED TIMING BEFORE
RECENTLY? CONTINUING.
NO
WITH THE DRB, ATTEMPT TO START READ CODES. DOES
ERASE CODES. ENGINE AND THE DRB DISPLAY YES CONTINUE TEST
INCREASE ENGINE "TIMING GOVERNING TC-86A ON THE
TURN IGNITION OFF SPEED ABOVE 1000 POSITIVE GOVERNOR NEXT PAGE.
FOR 10 SECONDS. RPM. DEVIATION"?
NO
USE THE SCHEMATIC AS DOES THE DRB REPAIR THE HARNESS
A GUIDE AND WIGGLE MONITOR THE DRB DISPLAY "TIMING YES OR CONNECTOR THAT
THE SENSOR CONNECTOR DISPLAY. GOVERNING POSITIVE CAUSED THE CODE TO
& HARNESS. GOVERNOR SET.*
FIG.1 DEVIATION"?
NO
AT THIS TIME, THE USING THE
CONDITION REQUIRED SCHEMATIC AS A WERE ANY PROBLEMS YES REPAIR AS
TO SET THE CODE IS GUIDE, INSPECT THE FOUND? NECESSARY.*
NOT PRESENT. WIRING AND
FIG.2 CONNECTORS.
NO
REFER TO GENERAL
INFORMATION 3.3.2 YES
FOR ADDITIONAL TEST COMPLETE.*
INFORMATION ON
INTERMITTENT CODES.
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