GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2001 🢒 Yukon - 2WD 🢒 Suspension 🢒 Real Time Damping (RTD) 🢒 DTC C0551

Circuit Description

The suspension control module performs internal checks on the software (calibrations) contained in the EEPROM to ensure valid operation.

Conditions for Running the DTC

Upon key on and reset.

Conditions for Setting the DTC

The suspension control module detects internal problems with software (calibrations).

Action Taken When the DTC Sets
    • Disable all functions, (EVO, Rear Leveling and RTD).
    • The SERVICE RIDE CONTROL message will be displayed.
    • Stores a DTC C0551 in the suspension control module memory.

Conditions for Clearing the DTC
    •  Using the scan tool.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

Diagnostic Aids

Important:  Calibrate the suspension control module twice before replacement and cycle the ignition off and on to see if the DTC C0551 resets.

The replacement suspension control module must be calibrated when replacement is necessary.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Checks for other stored DTCs

  2. Checks to determine if DTC C0551 will re-set.

Step

Action

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you perform the RTD Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Real Time Damping

2

  1. Connect a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Select the Suspension Control Module display DTCs function on the scan tool.

Are there any other DTCs than C0551?

Go to Diagnostic Trouble Code (DTC) List

Go to Step  3

3

  1. Use the scan tool in order to clear the DTCs.

    2. Important: Use the scan tool to perform the set up procedure (re-calibrate) located under Special Functions (F8: Recalibration) for the suspension control module.

  2. Use the scan tool to re-calibrate the suspension control module.
  3. Road test the vehicle.
  4. Select the Suspension Control Module display DTCs function on the scan tool.

Does the scan tool display DTC C0551?

Go to Step 4

Go to Diagnostic System Check - Real Time Damping

4

Important: After replacement, use the scan tool to perform the set up procedure (re-calibrate) located under Special Functions (F8: Recalibration) for the suspension control module.

Replace the suspension control module. Refer to Electronic Suspension Control Module Replacement .

Did you complete the replacement?

System OK

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