GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2005 🢒 Yukon XL - 2WD 🢒 Accessories 🢒 Navigation Systems 🢒 DTC C0550

Circuit Description

The electronic suspension control (ESC) module performs internal checks on hardware and software calibrations to ensure valid operation.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0550 Electronic Control Unit (ECU) Performance

Conditions for Running the DTC

Upon key on with the ignition in the ON/RUN position.

Conditions for Setting the DTC

The ESC module detects an error with its microprocessor.

Action Taken When the DTC Sets
    • Disable all functions, rear leveling and ESC.
    • The SERVICE RIDE CONTROL message will be displayed.
    • Stores a DTC C0550 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 and cycle the ignition Off and On to see if DTC C0550 resets. Repeat 2 times before replacement.
    • The replacement ESC module must be programmed when replacement is necessary.

Test Description

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

  1. Checking to verify the DTC will not reset.

  2. Replace the ESC module and program.

Step

Action

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Use the scan tool in order to clear the DTCs.
  2. Use the scan tool to perform the programming procedure for the electronic suspension control (ESC) module, located under SPECIAL FUNCTIONS -- Recalibration. Also perform the ALC trim set, located under SPECIAL FUNCTIONS -- ALC Trim set, if applicable.
  3. Turn OFF the ignition and wait 45 seconds.
  4. Turn ON the ignition, with the engine OFF.
  5. Select the ESC module display DTCs function on the scan tool.

Does the scan tool display DTC C0550?

Go to Step 3

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

3

Replace the ESC module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

System OK

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