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TEST TC-85ACONTINUED - REPAIRING - TIMING GOVERNING NEGATIVE GOVERNOR DEVIATION
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
NOTE: THIS CODE REPAIR OTHER CODES
TEST TC-85A WILL SET DUE TO ARE ANY OTHER YES FIRST. CLEAR THIS
CONTINUED FROM NOISE ON THE CODES SET? CODE AND REPEAT
PREVIOUS PAGE. NEEDLE MOVEMENT DIAGNOSIS.*
SENSOR CIRCUIT.
NO
TEST DRIVE
REPLACE THE FUEL VEHICLE. USING THE DOES THE DRB YES REPLACE THE ENGINE
INJECTION PUMP DRB, DISPLAY DISPLAY THIS CODE? CONTROL MODULE.*
ASSEMBLY. CODES.
NO
TEST COMPLETED.*
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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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TEST TC-86ACONTINUED - REPAIRING - TIMING GOVERNING POSITIVE GOVERNOR DEVIATION
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
NOTE: THIS CODE
TEST TC-86A WILL SET DUE TO
CONTINUED FROM LOW FUEL VOLUME TO
PREVIOUS PAGE. THE INJECTION
PUMP.
CHECK THE FUEL WERE ANY PROBLEMS YES REPAIR AS
SYSTEM FOR FOUND? NECESSARY.*
RESTRICTIONS.
NO
TEST DRIVE THE
REPLACE THE FUEL VEHICLE. USING THE DOES THE DRB NO
INJECTION PUMP DRB, DISPLAY DISPLAY THIS CODE? TEST COMPLETED.*
ASSEMBLY.* CODES.
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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TEST TC-91AREPAIRING - VEHICLE SPEED SENSOR TROUBLE CODES
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
START TEST USING THE DRB,
TC-91A ERASE CODES.
TEST DRIVE THE WITH THE DRB, READ DOES THE DRB YES CONTINUE TEST
VEHICLE. TROUBLE CODES. DISPLAY A VEHICLE TC-91A ON THE
SPEED SENSOR CODE? NEXT PAGE.
NO
TURN IGNITION OFF. INSPECT THE VSS
HARNESS CONNECTOR IS THERE EVIDENCE YES REPAIR OR REPLACE
DISCONNECT THE VSS TERMINALS.** OF TERMINAL DAMAGE TERMINALS AS
HARNESS OR CORROSION? NECESSARY.*
CONNECTOR.** FIG.1
NO
CHECK THE VSS THIS INTERFERENCE
HARNESS FOR COULD BE CAUSED BY IS THE VSS WIRING NO REPAIR AS
MIS-ROUTING THAT HIGH CURRENT ROUTED CORRECTLY? NECESSARY.*
COULD INDUCE CARRYING WIRES OR
INTERFERENCE. THE ALTERNATOR.
YES
AT THIS TIME, THE USING THE SCHEMATIC
CONDITION REQUIRED AS A GUIDE, WERE ANY PROBLEMS YES REPAIR AS
TO SET THE CODE IS INSPECTOR THE WIRING FOUND? NECESSARY.*
NOT PRESENT. AND CONNECTORS.
FIG.2
NO
REFER TO GENERAL
INFORMATION 3.3.2
FOR ADDITIONAL TEST COMPLETE.*
INFORMATION ON
INTERMITTENT CODES.
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TEST TC-91BREPAIRING - VEHICLE SPEED SENSOR TROUBLE CODES
Perform TEST TC-91A Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
USING THE DRB
START TEST RECONNECT THE VSS RAISE AND SUPPORT OSCILLOSCOPE
TC-91B. AND ECM HARNESS THE VEHICLE DRIVE FUNCTION SELECT
CONNECTORS. AXLE. "LAB SCOPE".
SET VOLTAGE RANGE USING THE
TO +10.0v. SET TIME RANGE TO OSCILLOSCOPE LEAD,
SET PROBE TO x10. 40ms/Div. BACKPROBE ECM
HARNESS CONNECTOR
FIG.1 FIG.2 CAVITY 51. FIG.3
START THE ENGINE. SHIFT TRANSMISSION
INTO FIRST GEAR
ENGAGE THE PARKING AND ALLOW THE
BRAKE. WHEELS TO ROTATE
AT IDLE SPEED.
NOTE: A VALID VSS DOES THE DRB
OBSERVE THE DRB SIGNAL WILL CYCLE DISPLAY THE 5.0 NO REPLACE THE
OSCILLOSCOPE HI TO LOW SIMILAR VOLT VSS SIGNAL VEHICLE SPEED
PATTERN. TO THE PATTERN CYCLING HI AND SENSOR.*
SHOWN IN FIGURE 2. LOW?
YES
REPLACE THE ENGINE
CONTROL MODULE.*
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TEST TC-94AREPAIRING - VEHICLE THEFT ALARM TROUBLE CODES
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
CHECK SKIS MODULE
START TEST FOR PROPER ARE THERE ANY SKIS YES PERFORM TEST
TC-94A. COMMUNICATION AND PROBLEMS? SK-1A.
TROUBLE CODES
BEFORE CONTINUING.
NO
USING THE DRB,
SELECT "ENGINE"
FROM THE MAIN
MENU.
DISPLAY THE DOES THE REPLACE THE ENGINE
VEHICLE COMPARE THE PROGRAMMED VIN NO CONTROL MODULE AND
IDENTIFICATION PROGRAMMED VIN TO MATCH THE VEHICLE PROGRAM THE
NUMBER (VIN). THE VEHICLE VIN. VIN? CORRECT VIN INTO
THE ECM.*
YES
USING THE DRB,
SELECT "BODY" THEN
"BODY COMPUTER".
DISPLAY THE DOES THE REPLACE THE BODY
VEHICLE COMPARE THE PROGRAMMED VIN NO CONTROL MODULE AND
IDENTIFICATION PROGRAMMED VIN TO MATCH THE VEHICLE PROGRAM THE
NUMBER (VIN). THE VEHICLE VIN. VIN? CORRECT VIN INTO
THE BCM.*
YES
CONTINUE TEST
TC-94A ON THE
NEXT PAGE.
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TEST TC-94ACONTINUED - REPAIRING - VEHICLE THEFT ALARM TROUBLE CODES
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
TEST TC-94A TURN IGNITION OFF. RECONNECT ONLY THE
CONTINUED FROM ENGINE CONTROL
THE PREVIOUS INSTALL THE DIESEL MODULE HARNESS
PAGE. POWER RELAY. CONNECTORS.
KEY ON. MEASURE
USE AN AMMETER IN AMPERAGE FROM BCM IS THE AMPERAGE NO REPLACE THE ENGINE
THE FOLLOWING HARNESS CONNECTOR BETWEEN 1.0 AND CONTROL MODULE.*
STEP. CAVITY 72 TO GROUND. 1.4 MA?
FIG.1
YES
KEY ON. USING THE DRB
OSCILLOSCOPE
RECONNECT THE BODY FUNCTION, SELECT
CONTROL MODULE "LAB SCOPE".
HARNESS CONNECTORS.
SET VOLTAGE RANGE SET TIME RANGE TO
TO +20.0V. SET 0.1S/DIV.
PROBE TO X10.
FIG.2 FIG.3
KEY ON. USING NOTE: A VALID
OSCILLOSCOPE LEAD, IMMOBILIZER SIGNAL
BACKPROBE ECM WILL CYCLE HI AND
HARNESS CONNECTOR LO SIMILAR...
CAVITY 38. FIG. 1
DOES THE DRB
TO THE PATTERN DISPLAY SHOW THE YES REPLACE THE ENGINE
SHOWN IF FIGURE 3. 12 VOLT CONTROL MODULE.*
IMMOBILIZER SIGNAL
CYCLING HI AND LO?
NO
REPLACE THE BODY
CONTROL MODULE.*
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TEST SK-1AIDENTIFYING SENTRY KEY IMMOBILIZER SYSTEM PROBLEMS
NOTE:The Sentry Key Immobilizer System (SKIS) diagnosis may require usage of the customer's
additional keys to verify the cause of the system failure. In the event that the Sentry Key Immobilizer
Module (SKIM) needs replacing, all of the keys previously programmed into the SKIM's memory
must be programmed into the new SKIM.THEREFORE IT IS IMPORTANT THAT ALL OF THE
CUSTOMER'S KEYS PROGRAMMED FOR THE VEHICLE BE OBTAINED PRIOR TO BEGIN-
NING VEHICLE DIAGNOSIS.
NOTE:It is necessary to obtain the four-digit Personal Identification Number (PIN) from the
customer or the vehicle invoice. The PIN is required to perform certain SKIM tasks using the DRB.
NOTE:It is very important that the ECM/BCM is programmed with the correct Vehicle Identification
Number (VIN). Incorrect VIN programming may result in incorrect diagnosis and unnecessary
component replacement. Use the DRB to verify the correct VIN and country code are programmed
into the SKIM.
1. The battery must be fully charged for any test in this manual.
2. Attempt to start the engine. Crank for up to 10 seconds if necessary.
3. Connect the DRB to the diagnostic connector and select ``Theft Alarm'' then ``SKIM''.
If the DRB displays ``No Response''..................................perform test 1B
NOTE:If the DRB screen is blank or has a DRB error message displayed, go toGeneral
Information Section 3.5in this manual.
4. With the DRB, read and record SKIM trouble codes.
5. If diagnostic trouble code are displayed, refer to the diagnostic trouble code list on the next page
for the appropriate test.
NOTE:For all component locations, seeGeneral Information Section 4.0in this manual.
DIAGNOSTIC TROUBLE CODE (DTC) DISPLAYED
DIAGNOSTIC TEST
ANTENNA FAILURE**
COP FAILURE**
EEPROM FAILURE**
PCM STATUS FAILURE SK-2A
INTERNAL FAULT**
RAM FAILURE**
ROLLING CODE FAILURE SK-3A
SERIAL LINK EXTERNAL FAULT SK-4A
STACK OVERFLOW FAILURE **
TRANSPONDER COMMUNICATION FAILURE SK-5A
TRANSPONDER CRC (CYCLIC REDUNDANCY CHECK)
FAILURESK-6A
TRANSPONDER ID MISMATCH SK-7A
TRANSPONDER RESPONSE MISMATCH SK-8A
VIN MISMATCHSK-9A
**These trouble codes indicate an internal SKIM fault. Using the DRB, clear SKIM trouble code(s).
Perform several key cycles, leaving the key on for a minimum of 30 seconds per cycle. Using the
DRB, read SKIM trouble codes. If the trouble code is present, replace the SKIM.
NOTE:An intermittent start and stall condition accompanied with a transponder DTC can be caused
by the presence of a non-programmed key or key programmed to another vehicle, near the SKIM
antenna (ignition halo). This can occur if the customer has a key holder (ring) that contains more
than one key equipped with a transponder chip.
After replacement of the Sentry Key Immobilizer Module (SKIM) seeGeneral Information Section 8.0
for SKIM initialization.
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