DTC C0550: Ecu Malfunction

When ignition is turned on, RTD module monitors communication between its internal microprocessors and performs self diagnostic tests. If an internal malfunction is detected, RTD module will store DTC C0550 in its memory.

1. Perform RTD diagnostic system check. See RTD DIAGNOSTIC SYSTEM CHECK  under DIAGNOSIS & TESTING. After performing diagnostic system check, go to next step.
2. Replace RTD module. See RTD CONTROL MODULE  under REMOVAL & INSTALLATION.