Immobilizer System Cadillac CTS II

Fastener Tightening Specifications

Scheme 56

DIAGNOSTIC CODE INDEX

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Circuit/System Description

After a loss of battery power has been restored, the remote control door lock receiver (RCDLR) will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the RCDLR will run the VIN Timer for a programmable length of time, typically 10 minutes. The RCDLR will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the RCDLR will send the fuel disable password to the engine control module (ECM), via the serial data circuit. The immobilizer system considers this to be a tamper and will not allow the vehicle to start. The RCDLR will send a message via the serial data circuit to the IPC to flash the SECURITY indicator.

Substitution detection is based on correct response from the following modules: instrument panel cluster (IPC), export body control module (XBCM), driver door module (DDM), passenger door module (PDM). The modules compare their VIN to that stored in the VIN master on every ignition ON cycle and report their status to the theft deterrent module.

Conditions for Running the DTC

Ignition ON

Conditions for Setting the DTC

1. The VIN check flag of the RCDLR is true.
2. The RCDLR has determined that the battery has been reconnected after a battery disconnect.

Action Taken When the DTC Sets

1. The vehicle will not start.
2. The RCDLR sends the fuel disable message via the serial data circuit to the ECM.
3. The RCDLR will run the VIN Timer for a programmable length of time, typically 10 minutes.
4. The RCDLR sends a message to the IPC to illuminate the SECURITY indicator.

Conditions for Clearing the DTC

The RCDLR clears the current DTC when the correct VIN information is present.

Reference Information

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. With a scan tool, verify the stored VIN in the following modules matches the actual vehicle VIN: IPC XBCM DDM PDM If any modules stored VIN does not match the actual VIN, perform the setup procedure for that module. If the stored VIN does not match after setup, replace the module.
2. If all modules VIN match, replace the RCDLR.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for XBCM, RCDLR, IPC, DDM, PDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

After a loss of battery power has been restored, the theft deterrent module (TDM) will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the TDM will run the VIN Timer for a programmable length of time, typically 10 minutes. The TDM will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the TDM will send the fuel disable password to the engine control module (ECM), via the serial data circuit. The immobilizer system considers this to be a tamper and will not allow the vehicle to start. The TDM will send a message via the serial data circuit to the IPC to flash the SECURITY indicator.

Substitution detection is based on correct response from the following modules: instrument panel cluster (IPC), export body control module (XBCM), driver door module (DDM), passenger door module (PDM). The modules compare their VIN to that stored in the VIN master on every ignition ON cycle and report their status to the theft deterrent module.

Ignition ON

1. The VIN check flag of the TDM is true.
2. The TDM has determined that the battery has been reconnected after a battery disconnect.

1. The vehicle will not start.
2. The TDM sends the fuel disable message via the serial data circuit to the ECM.
3. The TDM will run the VIN Timer for a programmable length of time, typically 10 minutes.
4. The TDM sends a message to the IPC to illuminate the SECURITY indicator.

The TDM clears the current DTC when the correct VIN information is present.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. With a scan tool, verify the stored VIN in the following modules matches the actual vehicle VIN: IPC XBCM DDM PDM If any modules stored VIN does not match the actual VIN, perform the setup procedure for that module. If the stored VIN does not match after setup, replace the module.
2. If all modules VIN match, replace the TDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for XBCM, TDM, IPC, DDM, PDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

After a loss of battery power has been restored, the remote control door lock receiver (RCDLR) will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the RCDLR will run the VIN Timer for a programmable length of time, typically 10 minutes. The RCDLR will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the RCDLR will send the fuel disable password to the engine control module (ECM), via the serial data circuit. The immobilizer system considers this to be a tamper and will not allow the vehicle to start. The RCDLR will send a message via the serial data circuit to the IPC to flash the SECURITY indicator.

Substitution detection is based on correct response from the following modules: instrument panel cluster (IPC), export body control module (XBCM), driver door module (DDM), passenger door module (PDM). The modules compare their VIN to that stored in the VIN master on every ignition ON cycle and report their status to the theft deterrent module.

Ignition ON

1. The VIN check flag of the RCDLR is true.
2. The RCDLR has determined that the battery has been reconnected after a battery disconnect.

1. The vehicle will not start.
2. The RCDLR sends the fuel disable message via the serial data circuit to the ECM.
3. The RCDLR will run the VIN Timer for a programmable length of time, typically 10 minutes.
4. The RCDLR sends a message to the IPC to illuminate the SECURITY indicator.

The RCDLR clears the current DTC when the correct VIN information is present.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. With a scan tool, verify the stored VIN in the BCM matches the actual vehicle VIN. If VIN does not match, perform the BCM Programming/RPO Configuration procedure. If the BCM VIN does not match the actual VIN after programming, replace the BCM.
2. With a scan tool, verify the stored VIN in the following modules match the actual vehicle VIN: IPC XBCM DDM PDM If any modules stored VIN does not match the actual VIN perform the setup procedure for that module. If the stored VIN does not match after setup, replace the module.
3. If all modules stored VIN match the actual VIN, replace the RCDLR.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM, XBCM, RCDLR, IPC, DDM, PDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

After a loss of battery power has been restored, the theft deterrent module (TDM) will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the TDM will run the VIN Timer for a programmable length of time, typically 10 minutes. The TDM will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the TDM will send the fuel disable password to the engine control module (ECM), via the serial data circuit. The immobilizer system considers this to be a tamper and will not allow the vehicle to start. The TDM will send a message via the serial data circuit to the IPC to flash the SECURITY indicator.

Substitution detection is based on correct response from the following modules: instrument panel cluster (IPC), export body control module (XBCM), driver door module (DDM), passenger door module (PDM). The modules compare their VIN to that stored in the VIN master on every ignition ON cycle and report their status to the theft deterrent module.

Ignition ON

1. The VIN check flag of the TDM is true.
2. The TDM has determined that the battery has been reconnected after a battery disconnect.

1. The vehicle will not start.
2. The TDM sends the fuel disable message via the serial data circuit to the ECM.
3. The TDM will run the VIN Timer for a programmable length of time, typically 10 minutes.
4. The TDM sends a message to the IPC to illuminate the SECURITY indicator.

The TDM clears the current DTC when the correct VIN information is present.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. With a scan tool, verify the stored VIN in the BCM matches the actual vehicle VIN. If VIN does not match, perform the BCM Programming/RPO Configuration procedure. If the BCM VIN does not match the actual VIN after programming, replace the BCM.
2. With a scan tool, verify the stored VIN in the following modules match the actual vehicle VIN: IPC XBCM DDM PDM If any modules stored VIN does not match the actual VIN perform the setup procedure for that module. If the stored VIN does not match after setup, replace the module.
3. If all modules stored VIN match the actual VIN, replace the TDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM, XBCM, TDM, IPC, DDM, PDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

After a loss of battery power has been restored, the remote control door lock receiver (RCDLR) will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the RCDLR will run the VIN Timer for a programmable length of time, typically 10 minutes. The RCDLR will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the RCDLR will send the fuel disable password to the engine control module (ECM), via the serial data circuit. The immobilizer system considers this to be a tamper and will not allow the vehicle to start. The RCDLR will send a message via the serial data circuit to the IPC to flash the SECURITY indicator.

Ignition ON

1. The VIN check flag of the RCDLR is true.
2. The RCDLR has determined that the battery has been reconnected after a battery disconnect.

1. The vehicle will not start.
2. The RCDLR sends the fuel disable message via the serial data circuit to the ECM.
3. The RCDLR sends a message to the IPC to illuminate the SECURITY indicator.

The RCDLR clears the current DTC when the correct VIN information is present.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

With a scan tool, verify DTC B1016 is not set.

1. If DTC is set, program the RCDLR. If DTC resets, replace the RCDLR.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for RCDLR replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

After a loss of battery power has been restored, the theft deterrent module (TDM) will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the TDM will run the VIN Timer for a programmable length of time, typically 10 minutes. The TDM will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the TDM will send the fuel disable password to the engine control module (ECM), via the serial data circuit. The immobilizer system considers this to be a tamper and will not allow the vehicle to start. The TDM will send a message via the serial data circuit to the IPC to flash the SECURITY indicator.

Ignition ON

1. The VIN check flag of the TDM is true.
2. The TDM has determined that the battery has been reconnected after a battery disconnect.

1. The vehicle will not start.
2. The TDM sends the fuel disable message via the serial data circuit to the ECM.
3. The TDM sends a message to the IPC to illuminate the SECURITY indicator.

The TDM clears the current DTC when the correct VIN information is present.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

With a scan tool, verify DTC B1016 is not set.

1. If DTC is set, program the TDM. If DTC resets, replace the TDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for TDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information

The body control module (BCM) monitors the voltage input of the hood open switch signal circuit and the hood open closed switch signal circuit. With the hood open, the hood ajar portion of the switch is closed, grounding the hood ajar switch signal circuit from the BCM, and the hood closed portion of the switch is open. With the hood closed, the hood closed portion of the switch is closed, grounding the hood closed switch signal circuit from the BCM, and the hood ajar portion of the switch is open. During proper operation, the two separate voltage signals at the BCM should never be at the same voltage.

The BCM continuously monitors for this DTC

Both the hood open switch signal circuit and the hood closed switch signal circuit are simultaneously in an active or inactive state.

1. Remote start functions will be disabled.
2. The hood ajar switch inputs will be ignored by content theft deterrent (CTD).

1. A current DTC will clear when the conditions for setting are no longer present.
2. A history DTC will clear after 40 malfunction free ignition cycles.

Schematic Reference

1. «Immobilizer Schematics»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system)
2. «Remote Function Schematics»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#keyless-entry-system-and-remote-functions)

Connector End View Reference

Component Connector End Views

Description and Operation

Keyless Entry System Description and Operation (with RPO Y41) or Keyless Entry System Description and Operation (without RPO Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool BCM Hood Open Switch and Hood Closed Switch parameters. With the hood open, the Hood Open Switch parameter should read Active and the Hood Closed Switch parameter should read Inactive. With the hood closed, the Hood Open Switch parameter should read Inactive and the Hood Closed Switch parameter should read Active.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
2. Ignition OFF, test for less than 5 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, test for 11.5-12.0 volts between the signal circuit terminal A and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
4. Ignition ON, test for 11.5-12.0 volts between the signal circuit terminal B and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. If all circuits test normal, test or replace the hood ajar switch.

Component Testing

Hood Ajar Switch

1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
2. With the switch in the hood closed position, test for infinite resistance between the ground terminal C and the signal terminal A. If not infinite, replace the hood ajar switch.
3. Test for less than 2.0 ohms between the ground terminal C and the signal terminal B. If greater than the specified range, replace the hood ajar switch.
4. With the switch in the hood open position, test for infinite resistance between the ground terminal C and the signal terminal B. If not infinite, replace the hood ajar switch.
5. Test for less than 2.0 ohms between the ground terminal C and the signal terminal A. If greater than the specified range, replace the hood ajar switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Hood Primary and Secondary Latch Replacement»(/cadillac/cts/ii-2007-2014/remont/exterior-body-panels/#bolted-exterior-body-panels-and-closures)
2. «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

As part of the vehicle telematics enhanced services, a request may be sent to the remote control door lock receiver (RCDLR) to disable vehicle starting. If a valid message is received by the RCDLR requesting that starting be disabled, the start enable message will not be sent to the engine control module (ECM).

A valid start disable from telematics will set DTC B302A only as a history DTC.

Vehicle starting will be suspended and the security indicator will be illuminated.

1. A current DTC will clear when the telematic start disable request is no longer seen.
2. A history DTC will clear after 100 ignition cycles in which the telematic start disable request is not seen.

Diagnostic Aids

DTC B302A is only an indicator that a start disable request has been received from the vehicle telematics system and does not indicate a fault in the immobilizer system. B302A will only set as a history DTC.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Turn the ignition ON.
2. Observe the security indicator. After approximately 10 minutes, the indicator will turn off.
3. Turn the ignition OFF and wait 5 seconds.
4. Repeat steps 2-4 two more times for a total of 3 cycles or 30 minutes.
5. Turn the ignition ON. The start disable will now be cleared.
6. Using the Red Emergency Button, notify the OnStar advisor that the Ignition Block on the vehicle has been cleared and to update the account status.

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

As part of the vehicle telematics enhanced services, a request may be sent to the theft deterrent module (TDM) to disable vehicle starting. If a valid message is received by the TDM requesting that starting be disabled, the start enable message will not be sent to the engine control module (ECM).

A valid start disable from telematics will set DTC B302A only as a history DTC.

Vehicle starting will be suspended and the security indicator will be illuminated.

1. A current DTC will clear when the telematic start disable request is no longer seen.
2. A history DTC will clear after 100 ignition cycles in which the telematic start disable request is not seen.

DTC B302A is only an indicator that a start disable request has been received from the vehicle telematics system and does not indicate a fault in the immobilizer system. B302A will only set as a history DTC.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. With a master vehicle key, turn the ignition ON.
2. Observe the security indicator. After approximately 10 minutes, the indicator will turn off.
3. Turn the ignition OFF and wait 5 seconds.
4. Repeat steps 2-4 two more times for a total of 3 cycles or 30 minutes.
5. With a master vehicle key, turn the ignition ON. The start disable will now be cleared.
6. Using the Red Emergency Button, notify the OnStar advisor that the Ignition Block on the vehicle has been cleared and to update the account status.

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When learning a coded key, the theft deterrent module (TDM) is placed in learn mode. DTC B3031 will set automatically as an indicator that the system is in learn mode and not as a fault indicator. Once the coded key is learned, learn mode will be exited and the DTC cleared. If the TDM does not exit learn mode, B3031 will remain current and indicate a fault.

The immobilizer system is the learn coded keys state.

DTC B3031 will set any time the TDM enters the learn coded keys state.

The security indicator will illuminate.

1. A current DTC B3031 will be cleared upon the successful exit of learn mode.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41) or Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Verify DTC B3055 is not set. If the DTC is set, refer to «DTC B3055»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) .
2. Verify the scan tool TDM Learn Coded Key parameter displays Yes. If not the specified value, perform the 10 Minute Vehicle Key Relearn procedure. Refer to «Replacing Keys (North America except Canada)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) or «Replacing Keys (Canada, Europe, and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) .
3. Perform the 10 Minute Vehicle Key Relearn procedure. Refer to «Replacing Keys (North America except Canada)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) or «Replacing Keys (Canada, Europe, and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) . The TDM should exit the learn coded key state and DTC B3031 should clear. If the TDM does not exit the learn coded key state after the programming attempt, replace the TDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for TDM replacement, setup and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the theft deterrent module (TDM). The TDM then compares this value to a value stored in memory. This stored value is the learned key code. If the value is correct, the TDM will send the prerelease password via the serial data circuit to the engine control module (ECM). If the learned key code does not match or a transponder value is not received, the TDM will send the start disable password to the ECM.

Ignition is in the Accessory or Run position.

The TDM is unable to measure the ignition key transponder value.

1. Vehicle starting will be disabled.
2. The security indicator will be illuminated.

1. A current DTC will be cleared when the TDM detects a valid transponder value from the ignition key.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41) or Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Inspect all available vehicle keys that they are correct vehicle keys. If not a correct vehicle key, replace the key.
2. While viewing the scan tool TDM Transponder Key parameter, turn ON the ignition with each of the available vehicle keys. The parameter should read Present with all available keys. If only one key results in the parameter reading Not Present, replace the appropriate key. If all available keys result in the parameter reading Not Present, replace the TDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Replacing Keys (North America except Canada)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) or «Replacing Keys (Canada, Europe, and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system)
2. «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for TDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the theft deterrent module (TDM). The TDM then compares this value to a value stored in memory. This stored value is the learned key code. If the value is correct, the TDM will send the prerelease password via the serial data circuit to the engine control module (ECM). If the transponder value does not match the learned key code or a transponder value is not received, the TDM will send the start disable password to the ECM.

Ignition is in the Accessory or Run position.

The transponder value measured by the TDM is incorrect or not learned to the vehicle.

1. Vehicle starting will be disabled.
2. The security indicator will be illuminated.
3. The security indicator will flash (Canada only).

1. A current DTC will be cleared when the TDM detects a valid transponder value from the ignition key.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41) or Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Perform the 10-Minute Vehicle Key Relearn procedure. Refer to «Replacing Keys (North America except Canada)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) or «Replacing Keys (Canada, Europe, and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) .
2. While viewing the scan tool TDM Valid Key parameter, turn ON the ignition with each of the available vehicle keys. The parameter should read Yes with all available keys. If not the specified value, replace the appropriate key.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Replacing Keys (North America except Canada)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) or «Replacing Keys (Canada, Europe, and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system)
2. «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for TDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the theft deterrent module (TDM). The TDM then compares this value to a value stored in memory. This stored value is the learned key code. If the value is correct, the TDM will send the prerelease password via the serial data circuit to the engine control module (ECM). If the transponder value does not match the learned key code or a transponder value is not received, the TDM will send the start disable password to the ECM.

1. Ignition is in the Accessory or Run position.
2. A valid transponder value has been read.

1. The transponder value is valid and matches the value stored in the TDM memory.
2. The transponder calculation to the challenge from the TDM does not match the TDM calculation.

1. Vehicle starting will be disabled.
2. The security indicator will be illuminated.

1. A current DTC will be cleared when a valid transponder value has been read and authenticated.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41) or Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Replace the suspected inoperative or malfunctioning key. DTC B3935 should not reset and the vehicle should start.

1. If the replacement key results in the resetting of DTC B3935, replace the TDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Replacing Keys (North America except Canada)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) or «Replacing Keys (Canada, Europe, and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system)
2. «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for theft deterrent module replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the theft deterrent module (TDM) is in the learn coded key state, the TDM checks the current key to ensure it has been configured as a proper vehicle key.

1. Ignition is in the Accessory or Run position.
2. The TDM is in the learn coded key state.

The TDM has determined the current key is not configured as a proper vehicle key.

1. The security indicator will be illuminated.
2. Vehicle starting will be disabled.

1. A current DTC will be cleared when the TDM detects a properly configured vehicle key.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41) or Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

While viewing DTCs with a scan tool, attempt to start the vehicle using all of the available keys. The vehicle should start with all available keys.

1. If any key results in inoperative starting and DTC B3976 is set, replace the appropriate key.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Replacing Keys (North America except Canada) or Replacing Keys (Canada, Europe, and Asia)

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The remote control door lock receiver (RCDLR) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the RCDLR. Both the ECM and RCDLR perform a calculation on this challenge. If the calculated response from the RCDLR equals the calculation performed by the ECM, the ECM will allow vehicle starting.

Ignition is in the ACCESSORY or RUN position.

The calculated response from the RCDLR does not equal the calculation performed by the ECM.

1. The security indicator will illuminate.
2. Vehicle starting will be disabled.

1. A current DTC P0513 will be when a valid calculation is received.
2. A history DTC will be cleared after 40 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

The "key" referenced in the DTC descriptor does not refer to the vehicle key. In this case, "key" is referring to the challenge response.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (with RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The theft deterrent module (TDM) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the TDM. Both the ECM and TDM perform a calculation on this challenge. If the calculated response from the TDM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

Ignition is in the ACCESSORY or RUN position.

The calculated response from the TDM does not equal the calculation performed by the ECM.

1. The security indicator will illuminate.
2. Vehicle starting will be disabled.

1. A current DTC P0513 will be when a valid calculation is received.
2. A history DTC will be cleared after 40 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

The "key" referenced in the DTC descriptor does not refer to the vehicle key. In this case, "key" is referring to the challenge response.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (without RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When learning the prerelease password, as well as the challenge and response sequence, the engine control module (ECM) is placed in learn mode. DTC P0633 will set automatically as an indicator that the system is in learn mode and not as a fault indicator. Once the password and challenge/response are learned, learn mode will be exited when the engine is successfully started. If the ECM does not exit learn mode, P0633 will remain current and indicate a fault.

The ECM is in learn mode.

DTC P0633 will set any time the ECM enters learn mode.

The security indicator will illuminate.

1. A current DTC P0633 will be cleared upon a successful engine start after exit of learn mode.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

The "key" referenced in the DTC descriptor does not refer to the vehicle key. In this case, "key" is referring to the challenge response.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (with RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When learning the prerelease password, as well as the challenge and response sequence, the engine control module (ECM) is placed in learn mode. DTC P0633 will set automatically as an indicator that the system is in learn mode and not as a fault indicator. Once the password and challenge/response are learned, learn mode will be exited when the engine is successfully started. If the ECM does not exit learn mode, P0633 will remain current and indicate a fault.

The ECM is in learn mode.

DTC P0633 will set any time the ECM enters learn mode.

The security indicator will illuminate.

1. A current DTC P0633 will be cleared upon a successful engine start after exit of learn mode.
2. A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

The "key" referenced in the DTC descriptor does not refer to the vehicle key. In this case, "key" is referring to the challenge response.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (without RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When a Slow-Down request is sent from OnStar® the vehicle communication interface module (VCIM) sends a serial data message to the engine control module (ECM) indicating that reduced vehicle speed has been requested. Once the request is active the ECM begins reducing engine torque to match requested vehicle speed and a REDUCED ENGINE POWER indications is displayed. No DTCs will be set during this process.

The ECM monitoring the serial data message for specific validity traits. If the ECM determines that the validity of the message is in error DTC P162B will be set.

1. The engine run time is greater than 5 seconds.
2. No other serial data errors are present.

1. The VIN embedded in the Slow-Down serial data request does not match the VIN stored in the ECM.
2. The rolling code counter embedded in the Slow-Down serial data request does not increment for 10 consecutive messages.

1. ECM disregards all reduced vehicle speed request messages from the VCIM.
2. The ECM stores DTC P162B in ECM history.

1. The condition responsible for setting the DTC no longer exists.
2. A history DTC will clear after 40 malfunction-free ignition cycles have occurred.
3. A scan tool clear DTC request is performed.

Description and Operation

Remote Vehicle Speed Limiting Description and Operation (Stolen Vehicle Slow-Down)

Scan Tool Reference

Control Module References for scan tool information

If the DTC is set, perform the Stolen Vehicle Slow-Down Clear with a scan tool. If the DTC resets, replace the VCIM. If the DTC resets again, replace the ECM.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for VCIM and ECM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The remote control door lock receiver (RCDLR) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the RCDLR. Both the ECM and RCDLR perform a calculation on this challenge. If the calculated response from the RCDLR equals the calculation performed by the ECM, the ECM will allow vehicle starting.

Ignition is in the ACCESSORY or RUN position.

The ECM receives an incorrect prerelease password from the RCDLR.

1. The security indicator will illuminate.
2. Vehicle starting will be disabled.

1. A current DTC P1631 will be when a correct fuel enable password is received.
2. A history DTC will be cleared after 40 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (with RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The theft deterrent module (TDM) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the TDM. Both the ECM and TDM perform a calculation on this challenge. If the calculated response from the TDM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

Ignition is in the ACCESSORY or RUN position.

The ECM receives an incorrect prerelease password from the TDM.

1. The security indicator will illuminate.
2. Vehicle starting will be disabled.

1. A current DTC P1631 will be when a correct fuel enable password is received.
2. A history DTC will be cleared after 40 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (without RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The remote control door lock receiver (RCDLR) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the RCDLR. Both the ECM and RCDLR perform a calculation on this challenge. If the calculated response from the RCDLR equals the calculation performed by the ECM, the ECM will allow vehicle starting.

Ignition is in the RUN position.

A fuel disable signal from the RCDLR is received by the ECM.

1. The security indicator will illuminate.
2. Vehicle starting will be disabled.

1. A current DTC P1632 will be when a valid calculation is received.
2. A history DTC will be cleared after 40 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

The prerelease password sent to the ECM by the RCDLR is reliant on the communications between the transponder located in the vehicle key and the RCDLR. Failure to establish communications or an interruption in the communications between the vehicle key and the RCDLR will cause the fuel disable message to be sent and the setting of DTC B1632. DTC B3055 or B3060 will be set in the RCDLR. To properly diagnose DTC P1632, DTC B3055 or B3060 must be diagnosed and corrected first.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (with Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (with RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup and programming

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The theft deterrent module (TDM) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the TDM. Both the ECM and TDM perform a calculation on this challenge. If the calculated response from the TDM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

Ignition is in the RUN position.

A fuel disable signal from the TDM is received by the ECM.

1. The security indicator will illuminate.
2. Vehicle starting will be disabled.

1. A current DTC P1632 will be when a valid calculation is received.
2. A history DTC will be cleared after 40 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

The prerelease password sent to the ECM by the TDM is reliant on the communications between the transponder located in the vehicle key and the TDM. Failure to establish communications or an interruption in the communications between the vehicle key and the TDM will cause the fuel disable message to be sent and the setting of DTC B1632. DTC B3055 or B3060 will be set in the TDM. To properly diagnose DTC P1632, DTC B3055 or B3060 must be diagnosed and corrected first.

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer Description and Operation (without Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (without RPO Y41) . The ECM should successfully complete the password learn and the vehicle should start.

1. If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup and programming

Symptoms - Immobilizer

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) before using the symptom tables in order to verify that all of the following are true: There are no DTCs set. The control modules can communicate via the serial data links.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to «Immobilizer Description and Operation (without Y41)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system__immobilizer-description-and-operation-without-y41) or «Immobilizer Description and Operation (with Y41)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system) .

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the systems. Refer to «Checking Aftermarket Accessories»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__checking-aftermarket-accessories) .
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to Hood Ajar Indicator/Message Malfunction in order to diagnose the symptom.

Verification

Verify the vehicle is not in an OnStar initiated Stolen Vehicle Slow-Down mode. Look for a Reduced Engine Power message.

1. If in the Stolen Vehicle Slow-Down mode, perform the OnStar vehicle interface communication module (VCIM) Stolen Vehicle Slow-Down Clear with a scan tool. After performing the clear event procedure, press the Blue OnStar® button to inform the advisor that you need to be transferred to the Stolen Vehicle team to have the vehicle account updated.

1. Perform the «Diagnostic System Check - Vehicle»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/cadillac/cts/ii-2007-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The body control module (BCM) monitors the voltage input of the hood open switch signal circuit and the hood open closed switch signal circuit. With the hood open, the hood ajar portion of the switch is closed, grounding the hood ajar switch signal circuit from the BCM, and the hood closed portion of the switch is open. With the hood closed, the hood closed portion of the switch is closed, grounding the hood closed switch signal circuit from the BCM, and the hood ajar portion of the switch is open. During proper operation, the two separate voltage signals at the BCM should never be at the same voltage.

Schematic Reference

1. «Immobilizer Schematics»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system)
2. «Remote Function Schematics»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#keyless-entry-system-and-remote-functions)

Connector End View Reference

Component Connector End Views

Description and Operation

Keyless Entry System Description and Operation (with RPO Y41) or Keyless Entry System Description and Operation (without RPO Y41)

Electrical Information Reference

1. «Circuit Testing»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/cadillac/cts/ii-2007-2014/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, observe the scan tool BCM Hood Open Switch and Hood Closed Switch parameters. With the hood open, the Hood Open Switch parameter should read Active and the Hood Closed Switch parameter should read Inactive. With the hood closed, the Hood Open Switch parameter should read Inactive and the Hood Closed Switch parameter should read Active.

1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
2. Ignition OFF, test for less than 5 ohms between the ground circuit terminal C and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, test for 11.5-12.0 volts between the signal circuit terminal A and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
4. Ignition ON, test for 11.5-12.0 volts between the signal circuit terminal B and ground. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. If all circuits test normal, test or replace the hood ajar switch.

Hood Ajar Switch

1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
2. With the switch in the hood closed position, test for infinite resistance between the ground terminal C and the signal terminal A. If not infinite, replace the hood ajar switch.
3. Test for less than 2 ohms between the ground terminal C and the signal terminal B. If greater than the specified range, replace the hood ajar switch.
4. With the switch in the hood open position, test for infinite resistance between the ground terminal C and the signal terminal B. If not infinite, replace the hood ajar switch.
5. Test for less than 2 ohms between the ground terminal C and the signal terminal A. If greater than the specified range, replace the hood ajar switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Hood Primary and Secondary Latch Replacement»(/cadillac/cts/ii-2007-2014/remont/exterior-body-panels/#bolted-exterior-body-panels-and-closures)
2. «Control Module References»(/cadillac/cts/ii-2007-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for BCM or instrument cluster replacement, programming and setup

Scheme 57

10-Minute Immobilizer Relearn

This 10-minute relearn procedure will relearn the prerelease password and the challenge/response data between the theft deterrent module (TDM) and the engine control module (ECM).

1. Connect a scan tool to the vehicle in the pass-thru arrangement.
2. Turn ON the ignition, with the engine OFF.
3. Ensure that all power consuming devices are turned OFF on the vehicle.
4. On the Techline Terminal, select Service Programming System and follow the Techline Terminal on-screen instructions, using the Legacy Pass-Thru method. Ensure the correct programming selection is chosen based on component being replaced or programmed. For this procedure, go to the V.T.D. Vehicle Theft Deterrent Learn menu and choose the Vehicle Theft Deterrent Learn, ECM, or PK3 Replaced selection.
5. At this point the scan tool must remain connected for the duration of the 10-minute relearn procedure.
6. Observe the scan tool, after approximately 10 minutes the scan tool will display "Programming Successful, Turn OFF Ignition". The vehicle is now ready to relearn the key information and/or the passwords on the next ignition switch transition from OFF to CRANK.
7. Turn OFF the ignition and wait 2 minutes.
8. With a master vehicle key, turn the ignition to the RUN position for 15 seconds, then start the vehicle. The TDM and ECM have now relearned the pre-release password and the challenge/response data.
9. With a scan tool, clear any DTCs.

This 10-minute relearn procedure will relearn the fuel enable password between the remote control door lock receiver (RCDLR) and the engine control module (ECM).

1. Connect a scan tool to the vehicle in the pass-thru arrangement.
2. Turn ON the ignition, with the engine OFF.
3. Ensure that all power consuming devices are turned OFF on the vehicle.
4. On the Techline Terminal, select Service Programming System and follow the Techline Terminal on-screen instructions, using the Legacy Pass-Thru method. Ensure the correct programming selection is chosen based on component being replaced or programmed. Ensure the correct Vehicle Theft Deterrent Learn for Powertrain System selection is chosen based on the engine RPO of the vehicle being programmed.
5. At this point the scan tool must remain connected for the duration of the 10-minute relearn procedure.
6. Observe the scan tool, after approximately 10 minutes the scan tool will display "Programming Successful, Turn OFF Ignition". The vehicle is now ready to relearn the key information and/or the passwords on the next ignition switch transition from OFF to CRANK.
7. Turn OFF the ignition and wait 2 minutes.
8. Turn the ignition to the RUN position for 15 seconds, then start the vehicle. The RCDLR and ECM have now relearned the fuel continue password.
9. With a scan tool, clear any DTCs.

Adding Keys (Europe and Asia)

1. With the first previously learned vehicle key, turn ON the ignition, with the engine OFF.
2. Turn OFF the ignition and remove the key.
3. With the second previously learned vehicle key, turn ON the ignition, with the engine OFF.
4. Turn OFF the ignition and remove the key.
5. Within 10 seconds insert the key to be learned. Turn ON the ignition with the engine OFF. The vehicle has now learned the new key.

Adding Keys (North America)

1. With a previously learned master key, turn ON the ignition, with the engine OFF.
2. Turn OFF the ignition and remove the key.
3. Within 10 seconds of turning OFF the ignition, insert the key to be learned and turn ON the ignition. The vehicle has now learned the new key.

10-Minute Vehicle Key Relearn

This 10-minute learn procedure should be used when all vehicle keys are desired to be replaced or reprogrammed. This procedure will erase all previously learned vehicle keys from the TDM. Once the 10-minute learn procedure has been completed, any remaining vehicle keys may be programmed using the Adding Keys procedure to ensure their continued functionality.

1. Connect a scan tool to the vehicle in the pass-thru arrangement.
2. Turn ON the ignition, with the engine OFF.
3. Ensure that all power consuming devices are turned OFF on the vehicle.
4. On the Techline Terminal, select Service Programming System and follow the Techline Terminal on-screen instructions, using the Pass-Thru method. Ensure the correct programming selection is chosen based on component being replaced or programmed. For this procedure, go to the V.T.D. Vehicle Theft Deterrent Learn menu and choose the Vehicle Theft Deterrent Learn for Learning Replacement Keys selection.
5. At this point the scan tool must remain connected for the duration of the 10-minute relearn procedure.
6. Observe the scan tool, after approximately 10 minutes the scan tool will display "Programming Successful, Turn OFF Ignition". The vehicle is now ready to relearn the key information and/or the passwords on the next ignition switch transition from OFF to CRANK.
7. Turn OFF the ignition and wait 2 minutes.
8. With a master vehicle key, turn the ignition to the RUN position for 15 seconds, then start the vehicle. The TDM has now learned the key transponder information.
9. With a scan tool, clear any DTCs.

30-Minute Vehicle Key Relearn

This 30-minute learn procedure should be used when all vehicle keys are desired to be replaced or reprogrammed. This procedure will erase all previously learned vehicle keys from the TDM. Once the 30-minute learn procedure has been completed, any remaining vehicle keys may be programmed using the Adding Keys procedure to ensure their continued functionality.

1. With an unlearned master vehicle key, turn ON the ignition, with the engine OFF.
2. Observe the security indicator, after approximately 10 minutes the telltale will turn off.
3. Turn OFF the ignition, and wait 5 seconds.
4. Repeat steps 1-3 two more times for a total of 3 cycles or 30 minutes.
5. With a master vehicle key, start the vehicle. The vehicle has now learned the key transponder information.
6. If additional keys are required to be learned, refer to «Adding Keys (Europe and Asia)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system__adding-keys-europe-and-asia) or «Adding Keys (North America)»(/cadillac/cts/ii-2007-2014/remont/door-locks-anti-theft-systems/#immobilizer-system__adding-keys-north-america) .
7. With a scan tool, clear any DTCs.

This 10-minute learn procedure should be used when all vehicle keys are desired to be replaced or reprogrammed. This procedure will erase all previously learned vehicle keys from the TDM. Once the 10-minute learn procedure has been completed, any remaining vehicle keys may be programmed using the Adding Keys procedure to ensure their continued functionality.

1. Connect a scan tool to the vehicle in the pass-thru arrangement.
2. Turn ON the ignition, with the engine OFF.
3. Ensure that all power consuming devices are turned OFF on the vehicle.
4. On the Techline Terminal, select Service Programming System and follow the Techline Terminal on-screen instructions, using the Legacy Pass-Thru method. Ensure the correct programming selection is chosen based on component being replaced or programmed. For this procedure, go to the V.T.D. Vehicle Theft Deterrent Learn menu and choose the Vehicle Theft Deterrent Learn for Learning Replacement Keys selection.
5. At this point the scan tool must remain connected for the duration of the 10-minute relearn procedure.
6. Observe the scan tool, after approximately 10 minutes the scan tool will display "Programming Successful, Turn OFF Ignition". The vehicle is now ready to relearn the key information and/or the passwords on the next ignition switch transition from OFF to CRANK.
7. Turn OFF the ignition and wait 2 minutes.
8. With a master vehicle key, turn the ignition to the RUN position for 15 seconds, then start the vehicle. The TDM has now learned the key transponder information.
9. With a scan tool, clear any DTCs.

Immobilizer Description and Operation (without Y41)

The immobilizer system functions are provided by the theft deterrent module (TDM) and the engine control module (ECM). When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coil surrounding the ignition lock cylinder. This exciter coil is part of the TDM. The energized transponder transmits a signal that contains its unique value, which is received by the TDM. The TDM then compares this value to a value stored in memory. If the values match, the TDM will send the prerelease password via the serial data circuit to the ECM. If the transponders unique value is incorrect, the TDM will send the fuel disable password to the ECM.

When the ECM receives the TDM prerelease password, the ECM will challenge the password. The ECM sends this challenge back to the TDM via the serial data circuit. Both the ECM and TDM perform a calculation on this challenge. If the calculated response from the TDM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

The components of the theft system are as follows

1. TDM
2. ECM
3. Ignition key (Transponder)
4. Security indicator

Theft Deterrent Module (TDM)

Vehicles with steering column mounted ignition switches have the exciter integral with the theft deterrent module (TDM), which is located within the steering column. The TDM can learn up to 10 keys (transponder values).

The TDM uses the following inputs: battery voltage, ignition switched voltage and ground circuit. The theft deterrent control module uses the following outputs: password exchange and challenge/response with the engine control module (ECM).

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the TDM. The TDM then compares this value to the learned key code stored in memory. The TDM then performs one of the following functions

1. If the transponder value matches the values stored in the TDM memory, the TDM will send the prerelease password to the ECM via the serial data circuit.
2. If the transponders unique value does not match the value stored in the TDM, the TDM will send the fuel disable message to the ECM via the serial data circuit.
3. If the TDM is unable to measure the ignition key transponder value, the TDM will not send any messages to the ECM.

Engine Control Module (ECM)

When the engine control module (ECM) receives the theft deterrent module (TDM) prerelease password, the ECM will challenge the password. The ECM sends this challenge back to the TDM via the serial data circuit. Both the ECM and TDM perform a calculation on this challenge. If the calculated response from the TDM equals the calculation performed by the ECM, the ECM will allow vehicle starting.

The ECM will disable vehicle starting if any of the following conditions occur

1. The prerelease password is invalid.
2. The fuel disable password is sent by the TDM.
3. No passwords are received-There is no communication with the TDM.
4. The TDM calculated response to the challenge does not equal the calculation performed by the ECM.

The Ignition Key (Transponder)

The ignition key for Passkey III+ (PK3+) equipped vehicles is a standard ignition key with a transponder located in the plastic head of the key. The transponder value is fixed and unable to be changed. The immobilizer system uses the ignition key transponder value to determine if a valid ignition key is being used to start the vehicle. There are approximately 3 trillion possible transponder values. There are no visible electrical contacts. The keys are identified by + symbol in a circle stamped into the steel shank of the key. The immobilizer system use the following types of ignition keys

Master Keys

Master keys have a black plastic head for full access operation of the vehicle. Master keys may perform the following functions

1. Start the vehicle.
2. Lock/unlock all of the door locks and rear compartment.
3. Lock/unlock all of the storage compartments.

Valet Keys

Valet keys have a gray plastic head and are for restricted operation of the vehicle. Valet keys may perform the following functions

1. Start the vehicle.
2. Lock/unlock all of the door locks.

Fleet Keys

Fleets keys allow full access to the vehicle just as a master key would. However, unlike a master key which may only learn 10 keys to a particular vehicle, an unlimited number of fleet keys may be learned to the vehicle. Fleet keys are only used in vehicles configured for fleet use with RPO 6E2 or 6E8.

1. Start the vehicle.
2. Lock/unlock all of the door locks and rear compartment.
3. Lock/unlock all of the storage compartments.

Security Indicator

The theft deterrent module (TDM) can command the instrument panel cluster (IPC) to illuminate the security indicator only when the ignition key is in the ON position. The TDM will command the security indicator be illuminated any time a fault is noted in the immobilizer system and when the engine starting is disabled.

The immobilizer system is incorporated into the remote control door lock receiver (RCDLR). The immobilizer is provided in order to prevent the vehicle operation if an incorrect or unprogrammed keyless entry transmitter is used in an attempt to start the vehicle. When the brake is pressed or the ignition control knob is pushed in and rotated, the console passive antenna broadcasts a low frequency (LF) challenge to the transmitter. The transmitter will respond to the RCDLR via radio frequency (RF). If the RCDLR determines a valid transmitter has responded, vehicle starting will be allowed. This is accomplished by the RCDLR sending a fuel enable message to the engine control module (ECM).

The design of the immobilizer system is to prevent vehicle theft by disabling the engine unless the correct transmitter is present when attempting to start the vehicle. The system is similar in concept to conventional immobilizer systems which use a normal vehicle key. The components of the immobilizer system are as follows

1. Ignition mode switch
2. Key capture solenoid
3. Keyless entry transmitters
4. Console passive keyless entry antenna
5. Console active antenna
6. RCDLR
7. Security indicator
8. ECM

Ignition Mode Switch

The igniting mode switch is located at the right side of the steering column. The ignition mode switch is used to start the vehicle engine, turn OFF the vehicle, put the vehicle in ACC mode, or put the vehicle in RUN mode.

Key Capture Solenoid

The key capture solenoid allows the ignition control knob to be rotated through its various positions: OFF, ACCY, CRANK and RUN. The key capture solenoid is controlled by the RCDLR. Ground is applied to key capture solenoid through the park switch. If the vehicle is not in park, the solenoid will not be activated and the ignition control knob cannot be turned to the off position.

When the ignition control knob is pushed in or the brake pedal is pressed, the RCDLR looks for a valid transmitter on the interior of the vehicle. If a valid transmitter is detected, the RCDLR applies voltage to the key capture solenoid control circuit, which then allows the ignition control knob to be turned to the RUN position.

Keyless Entry Transmitter

The keyless entry transmitters are not only used to passively or actively lock and unlock the vehicle, they are also used to allow vehicle starting. If the RCDLR does not receive a valid RF response after the transmitter is challenged, the RCDLR will not send a fuel enable message to the ECM. If the RCDLR is unable to establish communication with the transmitter during an attempted engine start, the ELECTRONIC KEY NOT DETECTED message will display on the driver information center (DIC).

When any one of the programmed key fobs are challenged by pushing in the control knob, it will passively send a RF signal to the RCDLR. The RCDLR will then send a serial data message to the ECM to enable engine starting.

Keyless Entry Antenna - Console Passive

The console keyless entry antenna is located in the center console, under the cupholder. The purpose of the console keyless entry antenna is to send a low frequency RF challenge to a programmed transmitter within the interior of the vehicle when authentication is requested (brake pedal pressed or ignition control knob is pushed in). The console keyless entry antenna is controlled by the RCDLR.

The challenge from the console antenna can reach almost all areas inside the vehicle, with the exception of the rear package shelf. If the transmitter cannot be located inside the vehicle via the console antenna, the console active antenna is used.

If the RCDLR does not receive a valid response from a programmed transmitter, it will not allow the ignition control knob to rotate, and the DIC will display the message "ELECTRONIC KEY NOT DETECTED." See Electronic Key Not Detected

Keyless Entry Antenna - Console Active

The console active antenna is located in the center console. It has a small pocket next to it where the transmitter can be inserted if the transmitter battery is dead, weak, or the RF signal is being interrupted.

The purpose of the console active antenna is to detect a transmitter in the center console pocket when the transmitter cannot be detected inside the vehicle via the console antenna. It is only activated if the authentication sequence for starting has been attempted by the console passive antenna, but a transmitter has not be found. It is also used for programming transmitters. The console active antenna is controlled by the RCDLR.

If the RCDLR does not receive a valid response from a programmed transmitter, it will not allow the ignition control knob to rotate, and the DIC will display the message "ELECTRONIC KEY NOT DETECTED." See Electronic Key Not Detected

Remote Control Door Lock Receiver (RCDLR)

The RCDLR controls the console passive antenna and the console active antenna. The RCDLR also controls three other low frequency antennas used for passive vehicle entry, but not for immobilizer operations. The RCDLR will send an AC voltage signal and provide ground to the console active antenna when the ignition button is pressed and a transmitter is not found with the console passive antenna. This will enable the console active antenna to send out a low frequency broadcast challenge to a transmitter. The RCDLR also has an internal radio frequency (RF) antenna that receives the transmitter's responses. The RCDLR is responsible for sending the fuel enable message to the ECM if all the requirements are met.

The security indicator appears on the instrument panel cluster (IPC). If the security indicator flashes or is illuminated continuously during vehicle operation, a malfunction exists within the immobilizer system. The security indicator is a dual purpose indicator. With the ignition OFF, the indicator it is controlled by the body control module (BCM) as a status indicator for the content theft deterrent system. With the ignition ON, it is controlled by the immobilizer system as a fault indicator.

The RCDLR will turn on the indicator when any of the following conditions exist

1. DTC B3122 is active
2. DTC B1000 is active
3. A fuel disable response is received from the ECM.
4. The RCDLR loses communication with the BCM.

The RCDLR will flash the indicator when any of the following conditions exist

1. The VIN matching between the RCDLR and the other modules on the bus is not correct (export vehicles only)
2. The power mode has become RUN without the RCDLR authenticating a valid transmitter.

The ECM communicates with the RCDLR over the serial data line. If the RCDLR receives a valid transmitter RF response, the RCDLR allow the ignition to rotate to the RUN position and will send the fuel enable message to the ECM to enable the starting system. If the RCDLR does not receive a valid response from the transmitter, the ignition control knob will not rotate. Additionally, if the fuel enable password received by the ECM does match the stored password, vehicle starting will be disabled and the RCDLR will illuminate the security indicator.

Remote Vehicle Speed Limiting Description and Operation (Stolen Vehicle Slow-Down)

Certain vehicles equipped with OnStar® now have an additional feature that allows for remote limiting of the vehicle's speed. This OnStar® feature is called Stolen Vehicle Slow-Down and is now part of the OnStar® Stolen Vehicle Assistance service. This feature, when used in conjunction with local law enforcement and strict guidelines at the OnStar® Call Center, will slow the vehicle by interacting with the engine control system.

When the engine control system receives a valid request from the OnStar® telematics communications interface module, it will enter into a reduced engine power/vehicle speed limiting mode, which will decelerate the vehicle. Once the request is active the engine control module begins reducing engine torque to match requested vehicle speed and a REDUCED ENGINE POWER indication is displayed. No DTCs will be set during this process.

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• Component Connector End Views
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Control Module References
• Diagnostic Repair Verification
• Remote Function Schematics
• Keyless Entry System Description and Operation (without RPO Y41)
• Hood Primary and Secondary Latch Replacement
• Checking Aftermarket Accessories
• Steering Column Shroud Replacement (With Key Release Lever Knob)
• Ignition Lock Cylinder Replacement
• Fastener Caution
• DTC B0996 (with RPO Y41)
• Immobilizer Description and Operation (without Y41)
• Remote Vehicle Speed Limiting Description and Operation (Stolen Vehicle Slow-Down)
• Adding Keys (Europe and Asia)
• Adding Keys (North America)