Intermittent Starting Issue

[coza10]

My Mercedes E220 AMG Sports Coupe has an intermittent starting issue to date I've put a New Battery on(the old one was goosed) and changed the intermiate swictch behind the clutch. It is starting better but not right, Once it starts it generally is OK all day but sometimes with the odd instance that is refuses on first turn of the key. If it has been stood overnight and I go to start it the following can happen

1. Put clutch in, turn key - No lights at all on dashboard
2. Switch it off, lock the car, open the car, insert key - No lights at all on dashboard
3. Follow STEP 2 - but then open the drivers door and close it firmly - Put Key and clutch in Turn it and the drivers side seat belt light comes on at position 1, turn to position 2 and the dashboard lights up, position 3 the car starts and away we go

Its infurating, frustrating etc as cars can be - if anyone else has had this issue or knows how to solve it, I would be eternally grateful for your advice

Thank you in anticipation

Robert Corran - you can also text me on 07803 048779 with solutions

[Robertb]

Might the ignition barrel have a fault?

[coza10]

Hi Robert

Thank You

Not sure but the ignition barrell was replaced just over a year ago so don't think its that, when it had that fault a year ago couldn't get a thing to work on it, Handbrake even wouldn't come off. I think its definitely an Electrical issue maybe a module not working properly. The thing is when it does start it runs like a dream

[paul_c123]

Does it start okay with the 2nd key?

[coza10]

Same issue with both keys

[Smint]

On older MBs (W124s, we had several) such issues were often the overvoltage protection relay going wrong, to the point it was worth keeping a spare relay in the glove box.
Whether that's still a thing on more modern Benz i don't know.

[coza10]

Thanks Smint I have relayed this to my friend who is trying to get to the bottom of it