Key won't start car ? Every now and then ?

[alano]

Over the last 2 weeks now, about 4 or 5 times when I insert my key turn it all lights on dash but it won't turn over engin ?.
It's weird take key out wait 2 mins and it works fine. It's getting more frequent now and want to sort it before its compleatly goosed.
It's probably stupid but someone must have had this problem before ?

 

[Hatty]

I had a W203 with a similar intermittent problem, it turned out to be a faulty starter motor

 

[DSM10000]

Have you tried the spare key? also, when this happens do you get the normal gear selector display or is this part blank?

It could be the key, if automatic the gear position selector or the electronic ignition switch. A STAR doagnosis may help track it down. If automatic then next tine it happens try moving the gear lever from Park to Neutral and see if it works.

 

[d w124]

I`d say starter too

 

[DSM10000]

I`d say starter too

Electronic ignition switch problems cause very similar symptoms. STAR will record a communication error between the key and the Driver Authourisation System.

 

[EZS]

What does the key look like? worn or in OK condition?

 

[MB-BTurbo]

Electronic ignition switch problems cause very similar symptoms. STAR will record a communication error between the key and the Driver Authourisation System.

Will it recognise it when it works? I have exactly the same issue but can not predict when it will not work. Taking it to be looked at gives no guarantees that it will play up. Also can STAR work out if it is a starter motor issue rather than a electric ignition switch issue?

 

[grober]

Probably starter motor-- you can get a LUCAS reconditioned unit [ Usually a rebuild OEM Valeo] on exchange from ECP for about £120.

 

[SJX]

If there is a key error or immobiliser problem the dash usually indicates such, on my old 2000 W163 the display in the odo read something like 'incorrect key' if the ignition sensor loop occasionally misread the keycode chip. I tend to agree with other resonders that this sounds like a starter motor problem - Start cheap and get expensive later!!, check the wiring to the starter motor solenoid first, connect a test lamp to it, sit in the car and turn key to crank position, lamp should light.

Good luck Steve

 

[MB-BTurbo]

Mercedes in all their wisdom decided to put the starter motor in the most idiotic of places meaning its an engine out job. I dont think its a case of checking wires. Its not really convenient to check the wires or connect a lamp (although I dont really know what you mean).

 

[SJX]

Forget that - misread post... must get glasses fixed
Steve

 

[Tinkerer]

On mine the solution was that the battery voltage was dropping below 10.5V which meant that it generally did nothing, starter motor pulling tooooo much current and battery taking the strain!! changed both and all has been well since.

 

[jpwilliams]

Afraid that`s how my EIS problem started and it cost £500 to fix under warranty.
Regards
John

 

[MB-BTurbo]

Whats EIS and if it was under warranty why did you pay £500?

 

[alano]

Key problems

Thanks to every one who helped...
I am back from working
This time I was away for a couple of weeks so I am sorry I never got back to you all.
As it turns out most of you were right the starter motor was on the way out the thing just died on my yesterday. I had charged the battery put it all back in and nothing fu,&;:g ba,(;:d ing thing
Jacked up car
Spent 2 hours getting it off
Spent 3 hours getting it on ( beer/swearing )
Turned key and started
Then turned about 20 times all ok
Removed jack drove for 20 mins
Then started car again
Been driving all day stops and starting ok
Got a good deal from my Lucas shop
£140 swap for old
So far so good. The spare key was new I ment to say earlier sorry.
Thanks for everyone's advice ( start cheap was the best )
Thanks again.....

 

[jpwilliams]

Afraid that`s how my EIS problem started and it cost £500 to fix under warranty.
Regards
John

Sorry,my bad wording I`m afraid.
EIS=electronic ignition switch.
Would have cost £500 had it not been under warranty.
Sorry for being unclear.
Regards
John

 

[MB-BTurbo]

My non intermittent starting problem finally stopped today. It refused to start after 1/2 hour of trying and around 30 attempts. Went home and called the RAC. Waited 1 hour and went back to meet them.

It started

So after a long talk about all the possibilities and looking at where the relays could be etc I signed the paper and went to drive home. It didnt start again. Finally, now I had someone who knew what they were looking for witnessing what was going on. He immediately identified the starter motor to be the culprit, whacked it and it started straight away.

At least I know what I am dealing with now and will be on to warranty direct next week to try and sort it out.

 

[MB-BTurbo]

What is the labour time for an engine out job on a B class? First I was quoted 4 hours now Ive been told its more like 10!

 

[LozML270]

I've had the odd issue where it turns over for a split second and stops and displays "start Error" on the dash. Does this sound like the starter motor is getting tired too?

I just turned the key back and turned again and it started fine, I just don't want to get stranded when it doesn't let me off the hook so lightly...

Due a service after this weeks adventures so will see how I get on this week, unless you advise immediate intervention...

Help!

 

[Chamberlain]

Over the last 2 weeks now, about 4 or 5 times when I insert my key turn it all lights on dash but it won't turn over engin ?.
It's weird take key out wait 2 mins and it works fine. It's getting more frequent now and want to sort it before its compleatly goosed.
It's probably stupid but someone must have had this problem before ?

Iv got same fault now it's only now and then I also get faults come up on dash but after i wait for bit like you then try again car starts and there is no faults on dash