GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 Yukon - 2WD 🢒 Suspension 🢒 Electronic Suspension Control (ESC) 🢒 DTC C0551

Circuit Description

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

Action Taken When the DTC Sets
    • Disable all functions, Rear Leveling and ESC.
    • The SERVICE RIDE CONTROL message will be displayed.
    • Stores a DTC C0551 in the ESC 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
    • Program the ESC module twice before replacement and cycle the ignition off and on to see if the DTC C0551 resets.
    • The replacement ESC module must be programmed when replacement is necessary. If the ESC module is not programmed after replacement, DTC C0551 is stored in the ESC module memory and will not clear until the module is programmed.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Checks for other stored DTCs.

    2.

  2. Checking to verify the DTC will not reset.

Step

Action

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you perform the ESC Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Electronic Suspension Control

2

  1. Connect a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Select the electronic suspension control (ESC) 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. Program the ESC module, refer to SPS.
  2. Using the scan tool, perform the ALC trimset under Special Functions-ALC Trimset.
  3. Clear DTC and operate vehicle within the conditions for running the DTC.

Does the DTC reset?

Go to Step 4

System OK

4
  1. Replace the ESC module. Refer to Electronic Suspension Control Module Replacement .
  2. Program the ESC module, refer to SPS.
  3. Using the scan tool, perform the ALC trimset under Special Functions-ALC Trimset.
  4. Clear DTC and operate vehicle within the conditions for running the DTC.

Did you complete the replacement?

System OK

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