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Suspension Control System - Suspension Damping Buick LaCrosse II

Electronic Suspension 6 illustrations ~3480 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Electronic Suspension Control Module Fastener9 N.m80 lb in
Electronic Suspension Front Vertical Accelerator Fastener9 N.m80 lb in
Electronic Suspension Rear Position Sensor Replacement Fastener6 N.m53 lb in

Fastener Tightening Specifications

Scheme 1

Scheme 1: Power, Ground, Data Communication And Indicators
Scheme 1: Power, Ground, Data Communication And Indicators

Scheme 2

Scheme 2: Sensors And Actuators
Scheme 2: Sensors And Actuators

Diagnostic Code Index

DTCDescription
DTC C0000DTC C0000 71 Vehicle Speed Information Circuit Invalid Data
DTC C0575, C0580, C0585, or C0590DTC C0575 02 Left Front Damper Actuator Circuit Short to Ground DTC C0575 04 Left Front Damper Actuator Circuit Open DTC C0575 0F Left Front Damper Actuator Circuit Signal Erratic DTC C0580 02 Right Front Damper Actuator Circuit Short to Ground DTC C0580 04 Right Front Damper Actuator Circuit Open DTC C0580 0F Right Front Damper Actuator Circuit Signal Erratic DTC C0585 02 Left Rear Damper Actuator Circuit Short to Ground DTC C0585 04 Left Rear Damper Actuator Circuit Open DTC C0585 0F Left Rear Damper Actuator Circuit Signal Erratic DTC C0590 02 Right Rear Damper Actuator Circuit Short to Ground DTC C0590 04 Right Rear Damper Actuator Circuit Open DTC C0590 0F Right Rear Damper Actuator Circuit Signal Erratic
DTC C0595, C0600, or C0605DTC C0595 02 Left Front Acceleration Sensor Circuit Short to Ground DTC C0595 05 Left Front Acceleration Sensor Circuit High Voltage/Open DTC C0595 0A Left Front Acceleration Sensor Circuit Too Slow Transitions DTC C0600 02 Right Front Acceleration Sensor Circuit Short to Ground DTC C0600 05 Right Front Acceleration Sensor Circuit High Voltage/Open DTC C0600 0A Right Front Acceleration Sensor Circuit Too Slow Transitions DTC C0605 02 Left Rear Acceleration Sensor Circuit Short to Ground DTC C0605 05 Left Rear Acceleration Sensor Circuit High Voltage/Open DTC C0605 0A Left Rear Acceleration Sensor Circuit Too Slow Transitions
DTC C0670 or C0675DTC C0670 02 Left Front Acceleration or Position Sensor Circuit Short to Ground DTC C0670 05 Left Front Acceleration or Position Sensor Circuit High Voltage/Open DTC C0670 0A Left Front Acceleration or Position Sensor Circuit Too Slow Transitions DTC C0675 02 Right Front Acceleration or Position Sensor Circuit Short to Ground DTC C0675 05 Right Front Acceleration or Position Sensor Circuit High Voltage/Open DTC C0675 0A Right Front Acceleration or Position Sensor Circuit Too Slow Transitions
DTC C0720DTC C0720 71 Engine Torque Management Feedback Signal Invalid Data
DTC C0870DTC C0870 03 Control Module Voltage Reference Output Circuit Low Voltage DTC C0870 07 Control Module Voltage Reference Output Circuit High Voltage

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Circuit/System Description

The wheel speeds are detected by active wheel speed sensors. Each wheel speed sensor receives a 12 V reference voltage from the electronic brake control module (EBCM) and provides an alternating current square wave signal to the EBCM. As the wheel spins, the EBCM uses the frequency of the square wave signal to calculate the wheel speed. The EBCM sends the wheel speed information as a high speed controller area network (CAN) serial data message. Modules connected to the high speed CAN circuit monitor for the vehicle speed information.

Conditions for Running the DTC

System voltage is between 9-16 V.

Conditions for Setting the DTC

A supervised periodic message that includes the wheel speed serial data has not been received.

Action Taken When the DTC Sets

The electronic suspension control is disabled for the duration of the ignition cycle.

Conditions for Clearing the DTC

A current DTC clears when the diagnostic runs and passes.

Reference Information

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/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

Ignition ON, observe the scan tool EBCM Wheel Speed Sensor parameters. The parameters displayed should be within 1.6 km/h (1 MPH) on all sensors when driving in a straight line at a speed greater than 20 km/h (13 MPH).

Circuit/System Testing

  1. Ignition ON, verify that DTC C0035, C0040, C0045, or C0050 is not present in the K17 Electronic Brake Control Module. If any listed DTC is present, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) .
  2. Replace the K19 Suspension Control Module and verify the DTC does not reset. If the DTC resets, replace the K17 Electronic Brake Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for module replacement, programming, and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information

CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Front Damper Actuator Control HighC0575 02C0575 04C0575 02C0575 0F
Right Front Damper Actuator Control HighC0580 02C0580 04C0580 02C0580 0F
Left Rear Damper Actuator Control HighC0585 02C0585 04C0585 02C0585 0F
Right Rear Damper Actuator Control HighC0590 02C0590 04C0590 02C0590 0F
Left Front Damper Actuator Control LowC0575 02C0575 04C0575 04C0575 0F
Right Front Damper Actuator Control LowC0580 02C0580 04C0580 04C0580 0F
Left Rear Damper Actuator Control LowC0585 02C0585 04C0585 04C0585 0F
Right Rear Damper Actuator Control LowC0590 02C0590 04C0590 04C0590 0F

The suspension control module commands variable levels of current to each shock absorber actuator in response to rough road, braking or abrupt steering maneuver driving conditions. The current variation is performed by pulse width modulation (PWM) of the system voltage. The suspension control module continuously measures the actual current of each actuator. When a deviation between commanded and actual current is detected, a DTC is set.

System voltage is between 9-16 V.

C0575 02, C0580 02, C0585 02, and C0590 02

  1. A short to voltage or short to ground on the control high circuit is detected.
  2. A short to ground on the control low circuit is detected.

C0575 04, C0580 04, C0585 04, and C0590 04

  1. An open circuit on the control high or control low circuit is detected.
  2. A short to voltage on the control low circuit is detected.

C0575 0F, C0580 0F, C0585 0F, and C0590 0F

An erratic current on the actuator circuit is detected.

  1. The electronic suspension control is disabled for the duration of the ignition cycle.
  2. The driver information center displays the SERVICE SUSPENSION SYSTEM message.
  1. A present DTC will clear on the next consecutive malfunction-free ignition cycle.
  2. A history DTC will clear after 41 consecutive malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/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, with a scan tool, command the Damper Actuator Increase and Decrease while observing the Damper Actuator Command parameter. The parameter should vary between 0-1 000 mA. Listen/feel the Q37 Shock Absorber Actuator. The component should activate when changing between the commanded states.

  1. Ignition OFF, disconnect the harness connector at the appropriate Q37 Shock Absorber Actuator.
  2. Perform this setup step in the following order: Connect a test lamp and ammeter in series between both Q37 Shock Absorber Actuator harness connector control circuit terminals. Ignition ON, with a scan tool, attempt to clear all K19 Suspension Control Module DTCs (codes may not clear).
  3. With a scan tool, command the Damper Actuator to Increase the amperage to approximately 400 mA and Decrease to 0 mA while comparing the ammeter displayed values and scan tool Damper Actuator Command parameter displayed values. Verify the following: The test lamp is illuminated. The ammeter displayed values and scan tool Damper Actuator Command parameter displayed values change and are simultaneously within 15 mA of each other. If the test lamp is not illuminated and/or the values are not within the specified range, test both control circuits for a short to voltage, short to ground, or open/high resistance. If all circuits test normal, replace the K19 Suspension Control Module.
  4. If all circuits test normal, test or replace the Q37 Shock Absorber Actuator.

Component Testing

Static Test

  1. Ignition OFF, disconnect the harness connector at the appropriate Q37 Shock Absorber Actuator.
  2. Test for 2-3 ohms between the Q37 Shock Absorber Actuator control terminals. If not within the specified range, replace the Q37 Shock Absorber Actuator.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Strut, Strut Component, or Spring Replacement»(/buick/lacrosse/ii-2009-2013/remont/suspension-front/#front-suspension-system)
  2. «Shock Absorber Replacement (GNE)»(/buick/lacrosse/ii-2009-2013/remont/suspension-rear/#rear-suspension-system) , «Shock Absorber Replacement (GNC)»(/buick/lacrosse/ii-2009-2013/remont/suspension-rear/#rear-suspension-system)
  3. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for suspension control module replacement, programming, and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Front Body Acceleration Sensor 5V ReferenceC0870 03C0595 05C0870 07
Right Front Body Acceleration Sensor 5V ReferenceC0870 03C0600 05C0870 07
Rear Body Acceleration Sensor 5V ReferenceC0870 03C0605 05C0870 07
Left Front Body Acceleration Sensor SignalC0595 02C0595 05C0595 05, C0870 07C0595 0A
Right Front Body Acceleration Sensor SignalC0600 02C0600 05C0600 05, C0870 07C0600 0A
Rear Body Acceleration Sensor SignalC0605 02C0605 05C0605 05, C0870 07C0605 0A
Left Front Body Acceleration Sensor Low ReferenceC0595 05
Right Front Body Acceleration Sensor Low ReferenceC0600 05
Rear Body Acceleration Sensor Low ReferenceC0605 05

The suspension control module supplies a 5 V reference voltage and a low reference to each body acceleration sensor. The body acceleration sensors supply a signal of 0.5-4.5 V to the suspension control module.

System voltage is between 9-16 V

C0595 02, C0600 02, and C0605 02

The signal voltage is less than 0.5 V for 1.5 s

C0595 05, C0600 05, and C0605 05

The signal voltage is greater than 4.5 V for 1.5 s

C0595 0A, C0600 0A, and C0605 0A

  1. The number of signal changes is less than specified value for 2.5 s.
  2. Vehicle speed is greater than 30 km/h (19 MPH)
  1. The electronic suspension control is disabled for the duration of the ignition cycle.
  2. The driver information center displays the SERVICE SUSPENSION SYSTEM message.
  1. A present DTC will clear on the next consecutive malfunction-free ignition cycle.
  2. A history DTC will clear after 41 consecutive malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/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 Vertical Body Acceleration parameters. The parameters should be 0 m/s 2 .

  1. Ignition ON, verify that DTC C0870 is not present. If the DTC is present, refer to «DTC C0870»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping) to diagnose that DTC prior to this diagnostic.
  2. Ignition OFF, disconnect the harness connector at the appropriate B162 Vertical Body Acceleration Sensor.
  3. Open/Close doors, and wait 60 s. Test for less than 5 ohms between the low reference circuit terminal 3 and ground. If greater than the specified value, test the low reference circuit for short to voltage or an open/high resistance. If the circuit tests normal, replace the K19 Suspension Control Module.
  4. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground. If less than the specified value, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K19 Suspension Control Module. If greater than the specified value, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K19 Suspension Control Module.
  5. Test for 4.8-5.2 V between the signal circuit terminal 2 and ground. 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 K19 Suspension Control Module. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K19 Suspension Control Module.
  6. If all circuits test normal, replace the affected B162 Vertical Body Acceleration Sensor.
  7. Verify the DTC does not reset. If the DTC resets, replace the K19 Suspension Control Module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Electronic Suspension Front Vertical Accelerometer Replacement - Upper»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping)
  2. «Electronic Suspension Rear Position Sensor Replacement»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping)
  3. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for suspension control module replacement, programming, and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Left Front Vertical Suspension Acceleration Sensor 5V ReferenceC0870 03C0670 05C0870 07
Right Front Vertical Suspension Acceleration Sensor 5V ReferenceC0870 03C0675 05C0870 07
Left Front Vertical Suspension Acceleration Sensor SignalC0670 02C0670 05C0670 05, C0870 07C0670 0A
Right Front Vertical Suspension Acceleration Sensor SignalC0675 02C0675 05C0675 05, C0870 07C0675 0A
Left Front Vertical Suspension Acceleration Sensor Low ReferenceC0670 05
Right Front Vertical Suspension Acceleration Sensor Low ReferenceC0675 05

The suspension control module supplies a 5 V reference voltage and a low reference to each vertical suspension acceleration sensor. The vertical suspension acceleration sensors supply a signal of 0.5-4.5 V to the suspension control module.

System voltage is between 9-16 V.

C0670 02 and C0675 02

The signal voltage is less than 0.5 V for 1.5 s.

C0670 05 and C0675 05

The signal voltage is greater than 4.5 V for 1.5 s.

C0670 0A and C0675 0A

  1. The number of signal changes is less than specified value for 2.5 s.
  2. Vehicle speed is greater than 30 km/h (19 MPH).
  1. The electronic suspension control is disabled for the duration of the ignition cycle.
  2. The driver information center displays the SERVICE SUSPENSION SYSTEM message.
  1. A present DTC will clear on the next consecutive malfunction-free ignition cycle.
  2. A history DTC will clear after 41 consecutive malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/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 Vertical Wheel Acceleration parameters. The parameters should be 0 m/s 2 when the vehicle is parked on a level surface.

  1. Ignition ON, verify that DTC C0870 is not present. If the DTC is present, refer to «DTC C0870»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping) to diagnose that DTC prior to this diagnostic.
  2. Ignition OFF, disconnect the harness connector at the appropriate B161 Vertical Suspension Acceleration Sensor.
  3. Ignition OFF, open/close doors, and wait 60 s. Test for less than 5 ohms between the low reference circuit terminal 3 and ground. If greater than the specified value, test the low reference circuit for short to voltage or an open/high resistance. If the circuit tests normal, replace the K19 Suspension Control Module.
  4. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground. If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K19 Suspension Control Module. If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K19 Suspension Control Module.
  5. Test for 4.8-5.2 V between the signal circuit terminal 2 and ground. 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 K19 Suspension Control Module. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K19 Suspension Control Module.
  6. If all circuits test normal, replace the B161 Vertical Suspension Acceleration Sensor. Verify the DTC does not reset. If the DTC resets, replace the K19 Suspension Control Module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Electronic Suspension Front Vertical Accelerometer Replacement - Lower»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping)
  2. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for suspension control module replacement, programming, and setup
  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The suspension control module receives high speed controller area network (CAN) message inputs from the engine control module (ECM) identifying the actual engine torque. The suspension control module utilizes this signal to control the vehicle ride characteristics.

System voltage is between 9-16 V

The suspension control module received invalid serial data from the ECM.

The electronic suspension control is disabled for the duration of the ignition cycle.

  1. The condition for setting the DTC is no longer present.
  2. A history DTC will clear after 41 consecutive malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/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 that no DTCs are present in the ECM. If any DTC is present, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) to diagnose that DTC prior to this diagnostic.
  2. Replace the K19 Suspension Control Module control module and verify the DTC does not reset. If the DTC resets replace the K20 Engine Control Module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for control module replacement, programming, and setup

  1. Perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/buick/lacrosse/ii-2009-2013/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»(/buick/lacrosse/ii-2009-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
5V ReferenceC0870 03C0595 05, C0600 05, C0605 05, C0670 05, C0675 05C0870 07
Low ReferenceC0595 05, C0600 05, C0605 05, C0670 05, C0675 05

The suspension control module supplies a 5 V reference voltage and a low reference to each body acceleration sensor and vertical suspension acceleration sensor. The body acceleration sensors and vertical suspension acceleration sensors supply a signal of 0.5-4.5 V to the suspension control module.

System voltage is between 9-16 V.

C0870 03

The suspension control module detected a short to ground on the 5 V reference circuit for 1.5 s.

C0870 07

The suspension control module detected a short to voltage on the 5 V reference circuit for 1.5 s.

  1. The electronic suspension control is disabled for the duration of the ignition cycle.
  2. The driver information center displays the SERVICE SUSPENSION SYSTEM message.
  1. A present DTC will clear on the next consecutive malfunction-free ignition cycle.
  2. A history DTC will clear after 41 consecutive malfunction-free ignition cycles.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
  2. «Connector Repairs»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/ii-2009-2013/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/buick/lacrosse/ii-2009-2013/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 Suspension Position Sensor 5 V Reference parameter. The parameter should be 4.8-5.2 V.

  1. Ignition OFF, disconnect the harness connectors at all 5 vertical body and suspension acceleration sensors.
  2. Ignition ON, test for 4.8-5.2 V between any one of the 5 V reference circuits terminal and ground. If less than the specified range, test all of the 5 V reference circuits for a short to ground. If the circuits test normal, replace the K19 Suspension Control Module. If greater than the specified range, test all of the 5 V reference circuits for a short to voltage. If the circuits test normal, replace the K19 Suspension Control Module.
  3. Test for 4.8-5.2 V between all 5 vertical body and suspension acceleration sensor signal circuits terminals and ground. 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 K19 Suspension Control Module. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K19 Suspension Control Module.
  4. Reconnect each acceleration sensor, one at a time, cycling the ignition OFF and then ON between each connection while observing the scan tool Suspension Position Sensor 5 V Reference parameter. Verify the parameter is between 4.8-5.2 V. If not within the specified range when a particular acceleration sensor is connected, replace that sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Electronic Suspension Front Vertical Accelerometer Replacement - Upper»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping)
  2. «Electronic Suspension Front Vertical Accelerometer Replacement - Lower»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping)
  3. «Electronic Suspension Rear Position Sensor Replacement»(/buick/lacrosse/ii-2009-2013/remont/electronic-suspension/#suspension-control-system-suspension-damping)
  4. «Control Module References»(/buick/lacrosse/ii-2009-2013/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for suspension control module replacement, programming, and setup

Scheme 3

Scheme 3: Electronic Suspension Front Vertical Accelerometer Replacement - Upper
Scheme 3: Electronic Suspension Front Vertical Accelerometer Replacement - Upper
CalloutComponent Name
1Electronic Suspension Front Upper Position Sensor Fasteners (Qty: 2) CAUTION: Refer to Fastener Caution Tighten 9 N.m (80 lb in)
2Electronic Suspension Front Vertical Accelerometer Procedure Disconnect the connector from the sensor.
CAUTION
Refer to Fastener Caution

Electronic Suspension Front Vertical Accelerometer Replacement - Upper

Scheme 4

Scheme 4: Electronic Suspension Front Vertical Accelerometer Replacement - Lower
Scheme 4: Electronic Suspension Front Vertical Accelerometer Replacement - Lower
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the front tire and wheel assemblies. Unlock and disconnect the wheel speed sensor harness electrical connector. Refer to Electronic Suspension Position Sensor Front Jumper Harness Disconnection .
1Electronic Suspension Front Position Sensor Fastener CAUTION: Refer to Fastener Caution Tighten 9 N.m (80 lb in)
2Electronic Suspension Front Vertical Accelerometer
CAUTION
Refer to Fastener Caution

Electronic Suspension Front Vertical Accelerometer Replacement - Lower

Scheme 5

Scheme 5: Electronic Suspension Control Module Replacement
Scheme 5: Electronic Suspension Control Module Replacement
CalloutComponent Name
Preliminary Procedure Remove the left side luggage compartment trim. Refer to Rear Compartment Side Trim Panel Replacement (without HP6) , Rear Compartment Side Trim Panel Replacement (HP6, Left Side) , Rear Compartment Side Trim Panel Replacement (HP6, Right Side) .
1Electronic Suspension Control Module Bracket Bolt CAUTION: Refer to Fastener Caution . Tighten 9 (80 lb in)
2Electronic Suspension Control Module Bracket
3Electronic Suspension Control Module Electrical Harness Connector
4Electronic Suspension Control Module Procedure For programming and setup information, refer to Control Module References .
CAUTION
Refer to Fastener Caution .

Electronic Suspension Control Module Replacement

Scheme 6

Scheme 6: Electronic Suspension Rear Position Sensor Replacement
Scheme 6: Electronic Suspension Rear Position Sensor Replacement
CalloutComponent Name
Preliminary Procedure Folder the back on left side of the backseat. Lift the front left side of the luggage compartment trim floor panel and also the damping material.
1Electronic Suspension Rear Position Sensor Replacement Fastener (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten 6 N.m (53 lb in)
2Electronic Suspension Rear Position Sensor
CAUTION
Refer to Fastener Caution .

Electronic Suspension Rear Position Sensor Replacement

Electronic Suspension Control Description and Operation

The electronic suspension control system individually controls the damping force of each of the 4 shock absorbers in order to keep the vehicle body as calm as possible. Changes of the damping forces can be accomplished within milliseconds. Suspension characteristics can be changed at any time by activating the sport mode or tour mode.

The electronic suspension control system consists of the following major components

  1. The suspension control module
  2. Three vertical body acceleration sensors
  3. Two front vertical suspension acceleration sensors
  4. Four shock absorber actuators which are integrated within the shock absorbers

The suspension control module controls the damping forces according to the following factors

  1. Vehicle speed
  2. Steering wheel position
  3. Engine torque
  4. Brake pressure
  5. Body and front wheels vertical acceleration

The suspension control module evaluates these inputs in order to separately control the shock absorbers, providing an enhanced ride and comfort level over the widest possible range of operating conditions.

Suspension Control Module

The suspension control module controls the system functions and detects failures. The suspension control module receives input information by vertical acceleration sensors that are directly connected to the module and by other systems through the serial data line. The suspension control module commands variable levels of current to each shock absorber actuator.

Vertical Acceleration Sensors

The suspension control module supplies a common 5 V reference and a ground circuit to each of the five vertical acceleration sensor. The vertical acceleration sensors supply a signal of 0.5-4.5 V to the suspension control module.

The three vertical body acceleration sensors are mounted left front, right front and rear. The two front vertical suspension acceleration sensors are mounted at the strut.

Shock Absorber Actuators

The shock absorber actuators are integrated within the shock absorbers. The electronic suspension control system uses a proportional valve that is located in the external bypass of the displacement module.

Adjustment is performed by current control. The current consumption is 0-1.8 A. The actuators respond to commands of the suspension control module within milliseconds.

Driver Information Center Message

The electronic suspension control system does not have a malfunction indicator, but uses the instrument cluster for the display functions instead. When the suspension control module detects a fault that sets a DTC, it sends a message on the serial data line to the instrument cluster, which will display the following message

SERVICE SUSPENSION SYSTEM

The suspension control module has the ability to store DTCs as current or history codes. Most electronic suspension control system malfunctions will display a message in the instrument cluster and set a DTC. As long as the DTC is present, the message will be displayed.

The suspension control module uses an ignition cycling diagnostic approach. Actions taken when a fault is detected will remain until the ignition is turned OFF, even if the fault condition is not present anymore.

If a fault is no longer present, the DTC will be stored as a history code. After 41 consecutive malfunction-free ignition cycles the DTC will be deleted.