Circuit Description
The internal fault detection is handled inside the control module. No external circuits are involved. DTC C0550 is set when an internal malfunction takes place within the control module.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C0550 Electronic Control Unit (ECU) Performance
This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to DTC Symptom Description .
DTC Symptom | DTC Symptom Descriptor |
|---|---|
00 | No Additional Information |
39 | Internal Electronic Failure |
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. This program runs even if the voltage is out of the valid operating range.
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
If equipped, the following module specific actions may occur:
| • | The antilock brake system (ABS) indicator turns ON. |
| • | The BRAKE warning indicator turns ON. |
| • | The electronic brake control module (EBCM) disables the ABS/dynamic rear proportion (DRP)/traction control system (TCS). |
| • | The driver information center (DIC) displays the power steering warning message No Steering Assist. |
| • | The TCS indicator turns ON. |
Conditions for Clearing the DTC
| • | A current DTC clears when the malfunction is no longer present. |
| • | A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction. |
Diagnostic Aids
| • | This DTC may be stored as a history DTC without affecting the operation of the module. If stored only as a history DTC and not retrieved as a current DTC, do not replace the module. |
| • | If this DTC is retrieved as both a current and a history DTC, replace the module. |
| • | If this DTC continues to set intermittently, replace the module. |
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Is the DTC retrieved as a current DTC? | Go to Step 3 | Go to Diagnostic Aids |
3 |
Important: Perform the programming or setup procedure for the module, if required. Replace the control module setting the DTC as current. Refer to Control Module References . Did you complete the replacement? | Go to Step 4 | -- |
4 |
Does the DTC reset? | Go to Step 2 | System OK |
