Mercedes ML Diesel Solar Sensor Fault and Heating Issue

I had something similar with my Mercedes ML heating and a sensor fault I would check the wiring harness and connector to the solar sensor itself My issue was a corroded connector causing intermittent contact

Thanks for the quick reply Could you tell me where the solar sensor and connector are located and if you used special tools to check the wiring

The solar sensor on my ML is on the dashboard near the windshield The connector is right underneath it I only needed a visual inspection and contact cleaner If you are not comfortable with electrical work a workshop is best

Your advice helped I inspected the connector and found corrosion Cleaning the contacts cleared the error code and the heating is working now Thanks for the help