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TEST NS-5ACHECKING THE ENGINE MECHANICAL SYSTEMS
Perform TEST NS-SEL Before Proceeding
NOTES
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TEST NS-5ACHECKING THE ENGINE MECHANICAL SYSTEMS
Perform TEST NS-SEL Before Proceeding
*Perform Verification TEST VER-1A. **Check connectors - Clean / repair as necessary.
KEY OFF. USING
START TEST SERVICE MANUAL IS THE VALVE NO REPAIR VALVE
NS-5A. PROCEDURES, CHECK TIMING WITHIN TIMING AS
ENGINE VALVE SPECIFICATIONS? NECESSARY.
TIMING.
YES
USING SERVICE
MANUAL PROCEDURES, IS ENGINE NO REPAIR THE ENGINE
CHECK ENGINE COMPRESSION WITHIN AS NECESSARY.
COMPRESSION. SPECIFICATIONS?
YES
USING SERVICE
MANUAL IS INJECTION PUMP NO REPAIR INJECTION
PROCEEDURES, CHECK TIMING WITHIN PUMP TIMING AS
INJECTION PUMP SPECIFICATIONS? NECESSARY.
TIMING.
YES
TEST COMPLETED.
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TEST VER-1ANO START VERIFICATION
Important Note:
If the Engine Control Module, Sentry Key Immobilizer Module or Body Control Module have been
changed the Vehicle Identification Number (VIN) and Secret Key data must be updated to enable the
vehicle to start and run. Refer to GENERAL INFORMATION SECITON 8.0 for programming
procedures.
Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect
components as necessary.
Inspect the engine oil for contamination. If it is contaminated, change the oil and filter.
Using the DRB, clear all diagnostic trouble codes (DTC's).
Turn the ignition off for 10 seconds.
Attempt to start the vehicle.
If the engine isunableto start, look for any Technical Service Bulletins that may relate to this
condition. Return toDTC TESTif necessary.
The repair is now complete.
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TEST VER-2AROAD TEST VERIFICATION
Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect
all components as necessary.
If this verification procedure is being performed after a NO TROUBLE CODE test, do the
following:
1. Check to see if the initial symptom still exists.
2. If the initial or another symptom exists, the repair is not complete. Check all pertinent Technical
Service Bulletins and return toTEST NTC-1Aif necessary.
For previously read trouble codes that have not been dealt with, return toDTC TESTand follow the
path specified; otherwise, continue.
If the engine control module has not been changed:
1. Connect the DRB to the data link connector and erase trouble codes.
2. With the DRB, reset all values in the adaptive memory.
3. Disconnect the DRB.
4. Turn the ignition off for at least 10 seconds.
Ensure no trouble code remains by doing the following:
1. If this test is for anA/C Relay Control Circuit,drive the vehicle for at least five minutes with
the A/C on. For some of the drive, go at least 40 mph; at some point stop the car and turn the
engine off for 10 seconds or more then restart and continue. Upon completion of the road test,
turn the engine off, and read trouble codes with the DRB.
2. If the repaired code has reset, the repair is not complete. Check all related Technical Service
Bulletins and return toDTC TESTif necessary. If another trouble code has set, return toDTC
TESTand follow the path specified for that trouble code. If there are no trouble codes, the
repair was successful and is now complete.
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TEST VER-3ASPEED CONTROL VERIFICATION
Inspect the vehicle to ensure that all engine components are connected. Reassemble and reconnect
all components as necessary.
If the engine control module has been changed, do the following:
1. If the vehicle is equipped with a factory theft alarm, start the vehicle at least 20 times so that
the alarm system may be activated when desired.
Connect the DRB to the data link connector and erase the codes.
Ensure no other speed control problems remain by doing the following:
1. Road test the vehicle at a speed above 35 mph.
2. Turn the speed control ON/OFF switch to the ON position.
3. Depress and release the SET switch. If the speed control did not engage, the repair is not
complete.*
4. Quickly depress and release the RESUME/ACCEL switch. If the vehicle speed did not increase
by 2 mph, the repair is not complete.*
5. Using caution, depress and release the brake pedal. If the speed control did not disengage, the
repair is not complete.*
6. Bring the vehicle speed back up to 35 mph.
7. Depress the RESUME/ACCEL switch. If the speed control did not resume the previously set
speed, the repair is not complete.*
8. Hold down the DECEL switch. If the vehicle did not decelerate, the repair is not complete.
9. Ensure the vehicle speed is greater than 35 mph and release the SET switch. If the vehicle did
not adjust and set a new vehicle speed, the repair is not complete.*
10. With Speed Control engaged, depress the ON/OFF switch. If the speed control did not
disengage, the repair is not complete.*
If the vehicle successfully passed all of the previous tests, the speed control system is now
functioning as designed. The repair is now complete.
*Check for Technical Service Bulletins that pertain to this speed control problem and then, if
necessary, return toDTC TEST.
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8.0 MAINTENANCE AND SERVICE INFORMATION
Refer to the appropriate service manual for information about repair and replacement procedures
When replacing a blown fuse, it is important to use only a fuse having the correct amperage rating.
The use of a fuse with a rating other than indicated may result in a dangerous electrical system
overload. If a properly rated fuse continues to blow, it indicates a problem in the circuit that must
be corrected.
NOTE:If it is necessary to replace the body controller and the SKIM, perform the following steps
in order:
± program the new body controller
± program the new SKIM
± replace all ignition keys, program new ignition keys to new SKIM
NOTE:If it is necessary to replace the engine control module and the SKIM, perform the following
steps in order:
± program the new SKIM
± program the new engine control module
8.1 Programming the Engine Control Module
1. To program the VIN, connect the DRB and turn ignition on.
2. Select ªENGINEº from the main menu. The DRB will request the SKIS four-digit PIN.
3. Enter the PIN.
4. Select ªENTERº to update the VIN. The DRB will display the updated VIN.
5. If the engine is equipped with air conditioning, the ECM a/c function must be enabled.
± Using the DRB select ªENGINEº, ªMISCELLANEOUSº then ªENABLE/DISABLE A/Cº.
± Push 1 to enable A/C. DRB screen should display ªA/C Activatedº.
8.2 Programming the Body Control Module
The SKIS ªSecret Keyº is an I.D. code that is unique to each SKIM. This code is programmed and
stored in the SKIM, body controller and transponder chip (ignition keys). When replacing the BCM
it is necessary to program the secret key into the new BCM using the DRB. Perform the following
steps to program the secret key into the body controller.
1. Turn the ignition on (transmission in park/neutral).
2. Use the DRB and select ``THEFT ALARM'', ``SKIM'' then ``MISCELLANEOUS''.
3. Select ``GS DIESEL BCM REPLACED''.
4. SELECT ªENTERº to update BCM VIN.
5. Enter secured access mode by entering the vehicle four-digit PIN.
NOTE:If three attempts are made to enter secure access mode using an incorrect PIN, secured
access mode will be locked out for one hour. To exit this lockout mode, turn the ignition to the RUN
position for one hour then enter the correct PIN. (Ensure all accessories are turned off. Also
monitor the battery state and connect a battery charger if necessary).
6. Press ªENTERº to transfer the secret key (the SKIM will send the secret key to the BCM).
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11.0 REQUIRED TOOLS AND EQUIPMENT
ammeter
DRB (diagnostic read-out box) scan tool
jumper wires and probes
ohmmeter
vacuum gauge
voltmeter
12.0 GLOSSARY OF TERMS
backfire,
popbackfuel ignites in either the intake or the exhaust system
BCMbody control module
cuts out,
missesa steady pulsation or the inability of the engine to maintain a consistent
rpm
DLCdata link connector (previously called ``engine diagnostic connector'')
detonation,
pre-ignitiona mild to severe ping, especially under loaded engine conditions
ECMengine control module
ECTengine coolant temperature sensor
EGRexhaust gas recirculation valve and system
generatorpreviously called ``alternator''
hard startThe engine takes longer than usual to start, even though it is able to
crank normally.
hesitation,
sag, stumbleThere is a momentary lack of response when the throttle is opened.
This can occur at all vehicle speeds. If it is severe enough, the engine
may stall.
IATintake air temperature sensor
lack of power,
sluggishThe engine has less than expected power, with little or no increase in
vehicle speed when the throttle is opened.
MILmalfunction indicator lamp
PDCpower distribution center
poor fuel
economyThere is significantly less fuel mileage than other vehicles of the same
design and configuration.
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rough,
un-stable or
erratic idle
stallingThe engine runs unevenly at idle and causes the engine to shake if it is
severe enough. The engine idle rpm may vary (called ``hunting''). This
condition may cause stalling if it is severe enough.
SKIMSentry key immobilizer module
SKISSentry key immobilizer system
start and
stallThe engine starts but immediately dies.
surgeengine rpm fluctuation without corresponding change in throttle position
sensor
SRCsignal range check
VSSvehicle speed sensorG
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