Intermittent Starting Problem

[GregE240]

Dunno if any of the 129 owners has had this problem before, but I thought I might ask before I go and see the dealer....

My 1990 500SL occasionally plays up when it is started. Basically, its like this:

You turn the key. Instrad of getting all of the dashboard lights light up before the starter motor engages, you get no lights. The starter will then turn, but the car will not start. Its as if the immobiliser is still activated.

You turn the key back to zero and try again. Sometimes you get the same problem, other times you get all the dash lights, and the car starts.

I've a feeling its going to be one of THOSE intermittent problems.....you know the sort.

Only history worth mentioning was that it was fine before I left the car for two weeks holiday - I've used the car since but I suppose it could be low battery? Roof goes up and down okay though....

Secondly, the problem is the same with both ignition keys....

Any ideas or advice most appreciated.

Thanks,
Greg

[jasohal]

I had the same prob with my car after not moving it for 10 days.

The problem was the battery - charged it up for a few hours on slow charge and it started up just fine.

I though the same thing - alarm/or immobiliser as the starter was not even cranking. Reason is that the starter requires a lot of power from the battery when starting the engine...

[GregE240]

That was my thought too.

I did mean to buy a battery conditioner before I went away but work went ballistic sadly.....not only that, but the previous owner said the car was sensitive to low charge in the battery.

I'll have to get that conditioner then....although saying that, I'm off dahn sarf this weekend so it will have a really good run. That might do the trick.

Thanks jasohal.

Greg

[GregE240]

I have just spoken to an MB specialist in Coventry about this. He was recommended by someone at MB Coventry, mainly because he knows R129s inside out and backwards.

He thinks it could be the ignition barrel on its way out. Need to telephone him later and book it in for some investigative work.

He is also going to look at my drivers door window problem.

Will keep this thread updated.

Greg