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I parked my car a few months ago, and between the weather and being out of town haven't driven it since. I went out to start it and... nothing. Obviously the battery right? I jumped it, the lights came on but it wouldn't crank. I took the battery out and had it tested for bad cells, came back perfect (its also a new battery.) This was all a month or so ago when i did this. I charged the battery up and its been sitting since then. I just checked the voltage and its still at a healthy 12.5

I've narrowed it to three possible culprits: Bad starter, bad key, bad ignition lock thingy.

My key is a bit worn and has occasionally hung up while trying to turn it but has always worked. (I should probably get a new one, at least a flat key, regardless.)

Am I on the right track? If i test the starter and it's good would you look at the key or the ignition lock next?

If I buy a new ignition lock how does the whole key situation work?

Thanks all!
 

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I tested the fuses but i didnt pull and reinstall. Ill try that.

Nope, not even a click. Everything else comes on. Bad relay? Seems to me that the relay isnt getting power? That's why I was leaning toward the ignition lock and related parts.

Is there a way to check the starter without lifting the car? It's so deep in there I cant reach it with a multimeter.
 

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Checked fuses 34 and 35. 35 is good, there was nothing in 34. I put one in just for ****s and giggles... nothing.

I am not sure if the engine is grounded. I need to get the car lifted so I can find the earth strap and test it. Is there another way to do this? My car is in a place where its a huge pain to work on. Lifting is possible, but for another weekend.
 

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Checked fuses 34 and 35. 35 is good, there was nothing in 34. I put one in just for ****s and giggles... nothing.

I am not sure if the engine is grounded. I need to get the car lifted so I can find the earth strap and test it. Is there another way to do this? My car is in a place where its a huge pain to work on. Lifting is possible, but for another weekend.



Maybe this is a dumb thought but if you get 12.5 V across the battery terminals, take the negative off the battery and check voltage between the +ve on the battery and some good grounding point on the chassis. If ok then check the voltage between the +ve on the battery and the free end of the negative while disconnected. Is there any difference?
 

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Maybe this is a dumb thought but if you get 12.5 V across the battery terminals, take the negative off the battery and check voltage between the +ve on the battery and some good grounding point on the chassis. If ok then check the voltage between the +ve on the battery and the free end of the negative while disconnected. Is there any difference?
Sounds like a plan to me. Ill try that tomorrow, thanks.
 

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I've removed the K40 a few times. It looks pristine. I know visual inspection isn't always adequate, but I don't seem to have the tell-tale k40 issues?

More specifics. lights and gauges all work. fuel pump primes. top goes up and down. windows work. central locking dash button doesnt seem to work? I press it and I hear the pump trying but nothing happens with the locks. All the locks lock and unlock when i use the key in the door. My fob has never worked for me.
 

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I would have thought the starter is quite easy to check. Put a voltmeter on the starter terminal and try to start the car. If you get a voltage when turning the key then a problem with the starter (or earth, of course).


Yes, I agree; K40 starting problems are usually accompanied by cooling fan running, which I guess you don't have.


I have read that key fob batteries are only required for central locking - not starting. There is a thingy in the key that the engine management system talks to but this doesn't require batteries in the key fob (security). It's not a common problem but you would need to search - I can't remember all the details. I don't know how you would test the communication between the engine management system and the key. I can only suggest searching and reading.



What do you mean by "My key is a bit worn and has occasionally hung up while trying to turn it but has always worked"? There are also several threads on here about the key barrel in the dash - tumblers and such like. The problem in this case is usually not being able to turn the key and non release of the steering lock, rather then not starting. Again, you would have to search.
 

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Hi,

SDS will check the Drive Authorisation, do not know of anything else that will, probably Snap On / Launch and over £1000 Autel will .................

Yes, Key Batteries do not need to even be fitted to start the Engine, the ring around the Ignition Lock induces a current to excite the Key Chip and read the # code from it, then it passes that on to F2SB Module and onwards to ME via CAN Bus, if all the # data agrees she will be un immobilised, i.e. Start Authorisation will be a big fat YES :wink:

The Keys Batteries only power the Keys RF for the Central Locking etc ;)

HTH, Cheers Dave
 

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Discussion Starter #15
Maybe this will help with that?
I would have thought the starter is quite easy to check. Put a voltmeter on the starter terminal and try to start the car. If you get a voltage when turning the key then a problem with the starter (or earth, of course).

Yep, it will be easy, I just can't get to it without getting the car on ramps or jack stands. Not impossible, just a pain in a dirt lot.

Yes, I agree; K40 starting problems are usually accompanied by cooling fan running, which I guess you don't have.


I have read that key fob batteries are only required for central locking - not starting. There is a thingy in the key that the engine management system talks to but this doesn't require batteries in the key fob (security). It's not a common problem but you would need to search - I can't remember all the details. I don't know how you would test the communication between the engine management system and the key. I can only suggest searching and reading.

Yep, My fob never worked - with new batteries and everything. Opened it up to check the internals and swapped everything to a new housing cuz I thought maybe the button contacts weren't working. Still didn't work. And yep, I transferred the RFID chip over to the new housing and Gorilla glued it in. I can even see a slight light whenever I press a button... no idea why it doesn't work. Ive also done the key syncing - the way described above and a host of others I found on other forums.

What do you mean by "My key is a bit worn and has occasionally hung up while trying to turn it but has always worked"? There are also several threads on here about the key barrel in the dash - tumblers and such like. The problem in this case is usually not being able to turn the key and non release of the steering lock, rather then not starting. Again, you would have to search.

Sometimes the key is a little hard to turn and I'll have to turn it back to pos 1 then back to start. I know, I need to install a new ignition lock with a new key before my key gets stuck for good. Just wanted to confirm that that is probably not the crux of the problem since I can actually get the key to turn to the start position.

I'm not home yet, so haven't gotten to try the ground checks, but I had another thought:
Ive heard the immobilizers can go bad. Is this something I should/could look into? Does the car turn on at all if its malfunctioning, or just not start?
Thanks for all the help you guys, this has been so annoying.
 

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If you turn the key and you hear a click under the bonnet (hood) the battery is not fit to turn the starter or the engine is seized. If you hear nothing the starter solenoid is either defective or the wires going to it are broken. It is basically an electrical relay so the power from the ignition key is the low amp switch to the solenoid and the thick wire from the battery to the solenoid and the solenoid to the starter is controlled by it.
 

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Discussion Starter #18
So I finally got everything ready to lift the car and really figure it out. Decided to give the starting one last try... started right up, strong as ever. (Obviously somethings still wrong, but the hardest problem to diagnose is the one with no symptoms.)

Been driving it off and on the past few weeks, but I went out today and the exact same thing started happening. Power to everything, but the starter solenoid won’t do anything.

Does this give anyone any more concrete ideas as to what the problem could be?
 

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So I finally got everything ready to lift the car and really figure it out. Decided to give the starting one last try... started right up, strong as ever. (Obviously somethings still wrong, but the hardest problem to diagnose is the one with no symptoms.)

Been driving it off and on the past few weeks, but I went out today and the exact same thing started happening. Power to everything, but the starter solenoid won’t do anything.

Does this give anyone any more concrete ideas as to what the problem could be?

As others have suggested something is loose and you are losing continuity somewhere. The solenoid isn't IMHO going on vacation and coming back to work.
 

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I don’t understand how to get a clear image of the attachment because my husband and I our also having the same issue with the RCL causing the car to NOT Start at all and when I click on the attachment it is super blurry!

Having RCL issues with my car too

Do you have any pictures of this?
 
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