Diagnostics of the immobilizing anti-theft system (Chevrolet Captiva 1)

Signs of malfunction - anti-theft system

Important: Before using the symptom charts, you must complete the following steps.

• There are no fault codes.
• Controllers can communicate via a serial communication line.

• Description and operation of the Theft Prevention System (CTD)
• Description and operation of the Vehicle Theft Deterrent (VTD) system

• Inspect for aftermarket equipment that may affect the operation of the anti-theft system.
• Inspect easily accessible and visible parts of the system for obvious signs of damage or conditions that could lead to malfunction.

Intermittent fault

List of signs of malfunction

• Theft Deterrent (CTD) - Panic Mode Not Working
• Theft Deterrent (CTD) - Cannot be disabled with key
• The sound signal does not work in the alarm mode of the theft deterrent system (CTD)
• Lighting devices do not work in the alarm mode of the theft prevention system (CTD)

Theft Deterrent (CTD) - Panic Mode Not Working

Theft Deterrent (CTD) - Cannot be disabled with key

The sound signal does not work in the alarm mode of the theft deterrent system (CTD)

Lighting devices do not work in the alarm mode of the theft prevention system (CTD)

The anti-theft system indicator does not work

• An internal fault has been detected in the controller.
• Actions to Take When a DTC Sets
• The controller disables all additional inputs.

• The current fault code is cleared once the fault has disappeared.
• The fault code is cleared from the history when the ignition cycle counter in the controller reaches the reset threshold of 50 without the fault recurring.

• This DTC may be stored in the DTC history without affecting the operation of the controller.
• If the fault code is only stored in the log and is not issued as a current fault code, the controller should not be replaced.
• If the DTC is received both as a current DTC and as a stored DTC, replace the controller that generated the DTC.

• The VIN check flag in the anti-theft system controller is set to true.
• The anti-theft system controller detected that the battery was disconnected and then reconnected.

• The engine does not start.
• The theft deterrent control module sends a fuel inhibit command via the serial communication line to the ECM.
• The anti-theft system controller starts the VIN timer for a programmed period of time, usually 10 minutes.
• The anti-theft alarm controller sends a command to the BCM to turn on the SECURITY indicator.

• The anti-theft system controller clears the current trouble code when the correct VIN information is received.
• This DTC can be cleared using a scan tool.

• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• The current fault code is cleared once the fault has disappeared.
• The fault code is cleared from the history when the ignition cycle counter in the controller reaches the reset threshold without the fault recurring.

• If this DTC is received as current, replace the controller that set this DTC.

• The current DTC B3031 will be cleared after successfully exiting the learning mode.
• The history DTC will be cleared after 100 ignition cycles without a fault or when using a scan tool to clear DTCs.

Important: When performing the 10-minute or 30-minute relearn procedure, all keys not learned during this time will be deleted and will no longer be recognized. It is necessary to perform the add keys procedure with all keys or teach the customer how to perform the add keys procedure if not all keys are available during repair.

1. Verify that DTC B3060 is not set as current.
• If DTC B3060 has a current status, refer to "DTC B3060".
2. Using a scan tool, verify that the VTD Password Memory Enable parameter is set to YES.
• If the VTD Password Learn Enable parameter is not set to YES, perform the 10-minute relearn procedure for the powertrain system. See Theft Deterrent System Parts Programming.
3. Perform the 10-minute relearn procedure for the theft deterrent system (VTD). Refer to "Programming the Theft Deterrent System Parts". The immobilizer should exit the learn mode and DTC B3031 should be cleared.
• If the immobilizer does not exit the learning mode after attempting to program, the immobilizer should be replaced.

• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• The current DTC will be cleared when the immobilizer detects a valid transponder value from the ignition key.
• The history DTC will be cleared after 100 ignition cycles without a fault or when using a scan tool to clear DTCs.

Important: To ensure this diagnostic procedure is performed correctly, multiple keys for this vehicle are required. If only one key is available at the time of service, the customer should be contacted and asked to provide the remaining keys for service. If no other keys are available, a new spare key must be created.

1. Inspect all available, working keys for the vehicle.
• If any key does not fit the vehicle, it should be replaced.
2. While monitoring the trouble codes with the diagnostic tool, try to start the vehicle with each of the available keys. The vehicle should start with all available keys.
• If the engine fails to start with only one key and the current fault code B3055 is set, the faulty key must be replaced.
• If the engine fails to start with any of the available keys and the current fault code B3055 is displayed, the immobilizer must be replaced.

• Replacement of keys
• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• The current DTC will be cleared when the immobilizer detects a valid transponder value from the ignition key.
• The history DTC will be cleared after 100 ignition cycles without a fault or when using a scan tool to clear DTCs.

Important: To ensure this diagnostic procedure is performed correctly, multiple keys for this vehicle are required. If only one key is available at the time of service, the customer should be contacted and asked to provide the remaining keys for service. If no other keys are available, a new spare key must be created.

1. Perform the key replacement procedure.
2. Try to start the car engine. The car engine should start with all available keys.
• If the engine fails to start with any key, the faulty key must be replaced.

• Replacement of keys
• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• Ignition switch in Accessory position (Auxiliary) or Run.
• The immobilizer is in the code key memorization mode or additional key memorization mode

• The current fault code will be cleared when the immobilizer detects a correctly configured key for this vehicle.
• The history DTC will be cleared after 100 ignition cycles without a fault or when using a scan tool to clear DTCs.

Important: To ensure this diagnostic procedure is performed correctly, multiple keys for this vehicle are required. If only one key is available at the time of service, the customer should be contacted and asked to provide the remaining keys for service. If no other keys are available, a new spare key must be created.

• If the engine fails to start with either key and the current fault code B3976 is set, the faulty key must be replaced.

• Replacement of keys
• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• Ignition switch in Accessory position (Auxiliary) or Run.
• A valid transponder value was read.

• The transponder value is valid and matches the value stored in the immobilizer memory

• The current DTC will be cleared when a valid transponder value is read and authenticated.
• The history DTC will be cleared after 100 ignition cycles without a fault or when using a scan tool to clear DTCs.

• If the B3935 fault code is still displayed after replacing the key, replace the immobilizer.

• Replacement of keys
• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• The VIN check flag in the anti-theft system controller is set to true.
• The anti-theft system controller detected that the battery was disconnected and then reconnected.

• The engine does not start.
• The theft deterrent control module sends a fuel inhibit command via the serial communication line to the ECM.
• The anti-theft system controller starts the VIN timer for a programmed period of time, usually 10 minutes.
• The anti-theft alarm controller sends a command to the instrument cluster (IPC) to turn on the SECURITY indicator.

• The anti-theft system controller clears the current trouble code when the correct VIN information is received.
• This DTC can be cleared using a scan tool.

• Adding keys
• Replacement, adjustment and programming of the linked controller and the controller with communication failure.

• The voltage in the system is 9 - 16 V.
• The vehicle power mode master device requires serial data exchange to operate.

• The current fault code is cleared once the fault has disappeared.
• The fault code in the log is cleared when the ignition cycle counter in the controller reaches the reset threshold of 50 without the fault recurring.

• If there are multiple controllers with communication problems, select the one closest to the diagnostic connector (DLC).
• Some controllers do not have internal protection for certain voltage outputs and may cause the battery positive voltage fuse or ignition voltage supply to blow. If the input voltage fuse is blown but no short circuit is detected in that circuit, make sure there are no shorted to ground voltage output circuits on the controllers before replacing the controller.
• This diagnostic can be applied to any controller that must communicate over a high or low speed CAN serial link, provided the vehicle is equipped with an option that uses that controller.

Important: Only high-speed CAN controllers have a serial link enable circuit OR an auxiliary serial link wake-up circuit. If the controller with the communication problem does not have one of these circuits, go to step 4.

1. Turn ignition ON, verify that the test lamp illuminates between the serial data line enable circuit OR the auxiliary serial data line wake-up circuit and ground.
• If the test lamp does not light, repair the open or high resistance in the circuit. If there are no faults in the circuits, replace the BCM.
2. Turn on the ignition, check if the test lamp lights between all positive battery voltage circuits and ground.
• If the test lamp does not light, eliminate the short to ground or open/high resistance in the circuit. If the circuit fuse is blown, also check the positive voltage outputs on the controller for a short to ground. If the circuits are OK, replace the faulty controller.
3. Check if the test lamp lights between all ignition voltage circuits and ground.
• If the test lamp does not light, eliminate the short to ground or open/high resistance in the circuit. If the circuit fuse is blown, also check the positive voltage outputs on the controller for a short to ground. If the circuits are OK, replace the faulty controller.
4. Check that the resistance between the controller ground circuits and the ground is no higher than 1 Ohm.
• If it is higher than 1 Ohm, repair the open circuit in the ground circuit.
5. Determine if the controller with the communication problem is using a low speed CAN serial communication line.
• If the controller uses only high speed GMLAN communication line, replace the controller.
6. Check that the resistance in the low-speed CAN serial communication line between the controller with the communication problem and the controller generating the fault code is not higher than 1 ohm.
• If the resistance is greater than 1 ohm, check the low speed CAN serial communication line for an open or high resistance.
7. If all circuits are OK, replace the controller with communication problems.

• The voltage in the system is 9 - 16 V.
• The vehicle power mode master device requires serial data exchange to operate.

• The current fault code is cleared once the fault has disappeared.
• The fault code is cleared from the history when the ignition cycle counter in the controller reaches the reset threshold of 50 without the fault recurring.

• Using the above list of fault code definitions, determine which controller is experiencing communication problems.
• If there are multiple controllers with communication problems, select the one closest to the diagnostic connector (DLC).
• Some controllers do not have internal protection for certain voltage outputs and may cause the battery positive voltage fuse or ignition voltage supply to blow. If the input voltage fuse is blown but no short circuit is detected in that circuit, make sure there are no shorted to ground voltage output circuits on the controllers before replacing the controller.
• This diagnostic can be used on any module that is required to communicate over the high or low speed GMLAN serial data line, provided the vehicle is equipped with an option that uses that module.