I have a Mercedes E class (W211) 2003 reg. I have had a fault diagnosed. It’s the front passenger seat sensor pad which is causing the SRS light to come on. I have been told to solder a 3.9 ohm 1/4 watt resistor somewhere on the pad connector but I don’t know where. Can anyone help?

Check first that the airbag has not been accidentally switched off. As with many front seat passenger airbags, there is a switch to disarm it if you are using a rearward facing child seat. If memory serves me correctly, it may be in the glove box.