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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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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