SM5 Reduced Engine Power

I own a 2015 Renault SM5 with a gasoline engine. Recently, I've experienced reduced engine power. The error memory indicates a defective engine control unit (ECU). Mileage is at 233309 km. Is this a common issue with this model?

4 comment(s)

Ugh, ECUs! Sounds like a pain. I had a similar thing happen with my old Opel Astra a few years back. Reduced power, that sluggish feeling, right? For me, it turned out to be a faulty main relay messing with the voltage going to the ECU. Ever checked that?

Could you please elaborate on the process of checking the main relay? Is specialized equipment necessary, or is it a task that can be performed with basic tools?

Okay, so for me, the main relay was the culprit. Honestly, I wouldn't mess with it too much yourself unless you REALLY know what you're doing with automotive electronics. Control systems can be super sensitive. Best bet? Take it to a trusted mechanic. Tell them about the ECU error and mention the main relay as a potential issue. They'll be able to diagnose it properly and reset the system if needed.

The diagnosis confirmed a defective main relay, resulting in an ECU malfunction. The repair cost was 120€. The issue is now resolved.

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