DTC Code P0480 – What does this code mean for Mercedes?

<ul> <li><b>Engine Light ON (or Service Engine Soon Warning Light)</b>: The illumination of the engine light indicates a detected issue in the cooling fan control circuit. This is often the first sign of a malfunction in the cooling system.</li> <li><b>Engine Overheating</b>: The engine may overheat due to the cooling fan not operating correctly. This can be caused by a malfunction in the fan control circuit, leading to insufficient cooling.</li> </ul>

<ul><li>The fan control relay may be faulty, preventing proper operation of the cooling fan.</li><li>An open or shorted fan control relay harness can disrupt the electrical flow needed for the fan to function.</li><li>Poor electrical connections in the fan control relay circuit can lead to intermittent or complete failure of the cooling fan.</li><li>A malfunctioning cooling fan 1 can directly cause the control circuit to malfunction.</li><li>An open or shorted cooling fan harness can impede the necessary electrical signals for fan operation.</li><li>Poor electrical connections in the cooling fan circuit can result in unreliable fan performance.</li></ul>

<ul> <li><b>Initial Inspection</b>: Check the cooling fan fuse and relay for any signs of damage or corrosion. Ensure all connections are secure.</li> <li><b>Visual Inspection of Wiring</b>: Inspect the wiring harness for any signs of wear, damage, or disconnection. Pay special attention to the wiring near the cooling fan and control module.</li> <li><b>Check Cooling Fan Operation</b>: Manually activate the cooling fan using a scan tool to verify if the fan operates correctly. If the fan does not operate, it may indicate a faulty fan motor.</li> <li><b>Test Fan Relay</b>: Test the cooling fan relay by swapping it with a similar relay in the fuse box. If the fan operates with the swapped relay, the original relay is faulty.</li> <li><b>Measure Voltage at Fan Connector</b>: Use a multimeter to measure the voltage at the cooling fan connector. Ensure there is proper voltage supply when the fan is commanded on.</li> <li><b>Check Control Module</b>: Inspect the Engine Control Module (ECM) for any fault codes or issues. Ensure the ECM is sending the correct signal to the cooling fan relay.</li> <li><b>Final Verification</b>: Clear the DTC code and test drive the vehicle to ensure the issue is resolved and the code does not reappear.</li></ul>

<p>The DTC code P0480 indicates a Cooling Fan 1 Control Circuit Malfunction in Mercedes vehicles. This is a critical issue as it can lead to engine overheating.</p><ul><li><b>Immediate Actions:</b> Inspect the cooling fan relay, wiring, and control module.</li><li><b>Potential Risks:</b> Delayed repair can cause severe engine damage, leading to costly repairs.</li></ul>