2010 Cadillac CTS Sedan AWD V6-3.6L Page 720

2010 Cadillac CTS Sedan AWD V6-3.6L Page 720

DTC C0550

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptors

DTC C0550 00

- Electronic Control Unit (ECU) Performance

DTC C0550 31

- Electronic Control Unit (ECU) Performance

DTC C0550 32

- ECU Performance General Memory Failure

DTC C0550 34

- ECU Malfunction RAM Failure

DTC C0550 35

- ECU Malfunction ROM Failure

DTC C0550 36

- ECU Malfunction EEPROM Failure

DTC C0550 37

- ECU Malfunction Watch Dog failure

DTC C0550 38

- ECU Performance Supervision Software Failure

DTC C0550 39

- ECU Performance Internal Electronic Failure/Discard

DTC C0550 4B

- ECU Internal Fault

Circuit/System Description

When the ignition is turned ON, the microprocessor runs a diagnostic program to detect an internal fault when power up is commanded. If an

internal malfunction is detected, the control module will store a DTC C0550 in its memory.

Conditions for Running the DTC

The microprocessor runs a diagnostic program to detect an internal fault when power up is commanded. The only requirements are voltage and

ground.

Conditions for Setting the DTC

* The control module detects an internal write malfunction.

* The control module detects an internal checksum malfunction.

Action Taken When the DTC Sets

* The affected system warning indicator/warning message will activate.

* The affected system will be disabled.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the control module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Circuit/System Verification