SL has a mind of its own. somtimes

[hoppo4.2]

my old man has a 1999 sl 320 w124 i think (not to good with merc)

normaly every thing is fine its a fab car.

however somtimes when you turn the key you get no dash lights and it wont start.

somtimes you get half the light but not them all and it wont start

i cant really get an electriction to look at it becauce it will some times go months with out doing it.

normaly if you put the key in and out a few times i will work but yeaterday it took about 20 mins to get it going now its fine again.

anything common i should check first?

just dont want it to leave him stranded somewhere

many thanks

[ShadownINja]

Screams of a loose connection to me! (I'm in no way knowledgeable in car electronics.)

[Pentoman]

Check the battery connections are tight and consider a new battery.
Not a common sounding fault to me so I would at the very least check those to being with. Any chance it's been put away for the winter - if so that may add weight to the battery argument...

[Classy6]

Does it have 2 batteries? A starter & a supply battery?

If so, check the condition of the supply battery.