M Klasse bypass valve error and overheating

I had a similar issue with my M Klasse. Check if the engine overheating coincides with periods of reduced fuel efficiency. The bypass valve error could be triggered by another problem. Does it happen more often during particular driving conditions?

Thank you for your prompt response. Regarding your inquiry, I've noticed the engine overheating tends to occur during periods of sustained high-speed driving, which does seem to correlate with a marginal decrease in fuel efficiency. Did your instance of the bypass valve malfunction also present under similar conditions?

Yes, mine occurred under similar conditions. I would recommend visiting a workshop for a comprehensive diagnostic assessment. The error memory might point them in the right direction.

I appreciate your confirmation and advice regarding the workshop visit. The issue was indeed a faulty thermostat, causing the bypass valve error. The repair cost was 0€. Thank you for your time and help!