Please help.

Firstly may i appologise ...this is a long one


I've got a e320 CDi 2003 (60000 miles ish)

Last night i came out the sports centre, unlocked my car, put the key in, turned the ignition and nothing....would not crank over.(when I say nothing I DID seem to have all functioning electrics....it just wouldn't start)

I removed the key and tried again and then the ESP failure warning came up but the car still wouldn't start. Tried multiple times to start the car and nothing. After about the 10th time of trying to start it, another fault appeared, SRS failure restraint system de-activated. Still couldn't start the car. (The key would turn to the start position but it did nothing) I took the key out and tried again but this time I couldn't even turn the key to the first position. When I put the key in it made all the right noises (the noise it makes when you put the key in) but I still couldn't turn the key..

(BTW it was raining like mad outside)

Now this next bit your gonna laugh at (Because the roadside assistance guy did) but i am telling the gods honest truth !


After trying to start the damn thing 50 million times, I hit the steering wheel (basically whacked the horn) out of pure frustration. NOW THIS NEXT BIT IS VERY STRANGE. The minute I hit the horn I was able to turn key to the start position and IT STARTED ?????


Completely consfused I sat there for 5 minutes with the engine running and both the ESP and SRS fault disappeared. not knowing what the hell was going on, I phoned roadside assistance and told them I was gonna try and make it home (only 5 miles from where I was) and to cancel the service guy from coming out.

At this point I had to pop to my girlfriends to pick up some stuff which was literately round the corner.

When I got there I was in 2 minds whether to turn the car off in case it wouldn't start again. I decided I couldn't leave it running while I went into the house so I turned off the ignition and removed the key BUT as soon as I removed the key the horn sounded and would not shut off ?????. Immediately I put the key back in which stopped the horn from sounding and tried to turn the ignition to the first position but it would not turn and the ESP and SRS failures were showing up again.

Remembering the trick with pressing the horn to unlock the ignition and start the car I attempted it again and it started, only this time as it turned the key to the second position all the lights on the dash seemed to flicker rapidly and the ESP and SRS was complaining again.

Quite concerned I contacted MB roadside assistance again and told them what had happened and to get somebody out again quick.

As I was on the phone to them I decided I was gonna switch the car off and wait at my girlfriends house for them to arrive only to my HORROR.....when I removed the key from the ignition the CAR WAS STILL RUNNING......I COULDN'T TURN IT OFF. Panicking, I tried to put the key back into the ignition but it wouldn't turn to the first position, yet the car was RUNNING ....WITH NO KEY NEEDED. I tried the "pressing the horn" trick to try and get the key to turn to the first position but it would not move.


At this point I am totally confused. I have a car that WONT TURN OFF regardless what I did (At this point the key wasn't even in the ignition) and was showing ESP and SRS faults. As I was on the phone to MB service I explained the problem and they tried various sequences like putting it into neutral, holding foot on the brake and putting back into park but no luck. eventually they wanted me to remove the fuse for the motor (Motor stop) to cut the engine . He told me that I had to remove the cover inside the drivers door to remove a flap on the side of the dash which would give me the fuse mapping and look for the “motor stop” fuse.

As it was raining cats and dogs and pitch black outside I decided against that and thought ill just wait for roadside assistance. Only problem was I had to stay with the car cuz it wouldn't shut off.

NEXT , After sitting there for about 20 mins with the key in the ignition (Just inserted in the ignition not in any position) the car suddenly stopped and everything shut off. (it made me jump as I was daydreaming waiting for MB assistance)

After sitting there wondering what to do know I removed the key from the ignition, and proceeded to attempt to start the car, and it started...first time with no faults. Scratching my head I tried again and it started again first time no errors or faults. Not convinced I decided to leave it for 30 mins. I returned to the car and once again it started first time no errors.

this is truly unbelievable. The MB roadside guy is gonna appear and the damn this is now working. I decided to wait for him.. ONLY when he arrived he wasn't an MB mechanic , he was a third party MB were using. I wasted my time explaining the problem as after all the diagnosis he said I had re-programmed my key but putting it in trying to turn it on more than 9 times which he reckons re-programs your key that why I was having problems turning it to the first position. I totally disagreed and dismissed his diagnosis and mentioned that the guy on the phone was convinced I had water in my fuse box. He proceeded to take the cover off in the pitch black , hovered his hand over the fuse box and said that isn't wet

He then loosely put the cover back on the fuse compartment so I got rid of him and put it back on properly myslef

This morning, AFTER ALL this the car now seems fine and is behaving properly but for the life of me I cant begin to guess what’s wrong apart from what the guy on the phone said about water in the fuse box.



Can anybody throw any light on this little prob I’ve searched the forums and cant find anything similar?

How does water get into the fuse box ?
Has ANYBODY ever heard of anything like this…especially the bit about pressing the horn to get the key to unlock and start the car ?

I’ve heard of a COLD START, a WARM START, a WET START but never a HORN START !!

Im gonna take it to the dealership and get em to plug it in but i would like to go armed with some information if anybody has any advice as i am gonna look a total plum when i explain it to them.

Thanks in advance

Russ.

 

just spoke to dealer....they rekon its a faulty ignition switch ???

 

Meaning Electronic Ignition Switch control unit? Could be, if it stopped communicating with the rest of the car through CAN, the car could remain running without the key. Perhaps your hit on the steering wheel made a bad contact work in the unit?

Hope they only found fault codes from this one unit and replacing it will fix all malfunctions.

 

Finally i had a MB qualified service engineer just come out to me. The second he put the star diag onto the car he diagnosed that water had got into the SAM unit. He has removed it, cleaned out the remaining water residue, dried it out on his VAN heater and put it all back together again. He said that when i pressed the steering wheel it caused the system / electrics to "Short out / Surge" which enabled me to turn the car on. He mentioned that it's not the first time he's seen this fault on the E w211


He also said that the water in the sam unit caused the car to continue running without the key and has stated that it wouldn't cause any damage. Apparently on the new models there is an extra cover that sits on top of the fuse box cover, to stop any water entering the fuse box where the SAM unit is housed.

Basically the fuse box cover hadn't been seated correctly thus water has got into the unit. He rekons jetwashing the car can force water into the unit ?


Hope this info helps

Thanks to Diesel Benz and everyone else for your thoughts.
P.S that Star Diagnosis system......What a piece of kit that is....godda get me one

 

If I remember right, there was an issue with the rear light assembly that allowed water enter the trunk. But I believe this was for some later E-class cars.

Was it the rear SAM? I'd be a bit concerned about the water getting there, can it really come from decent power washing? Just wondering because you said it was raining heavily when the problem appeared.

Great anyway if the fault was properly identified.

 

WOW. Your experience is so weird that it's hard not to laugh, but you have my sympathies.

 

Unfortunately, it's not so weird considering it's an '03.

 

I know how that is.

 

Well, I had a similar problem, and i hope that this will enlighten future searchers.

There are 2 locations on the trunk water channel that feed the GPS/Teleaid antenna wires, one on each side. These are covered by black square covers right under the back window on each bottom corner. If you lift them up, you will see that each wire has an integrated rubber grommet that is attached to the metal.

Well, the left one on mine was completely out, and when I took it to a carwash, I would get stupid malfunctions, including SRS, no windows, no turn signals, and others. The SAM was soaked!

This happened twice, the first time I took it to the dealer and after diagnostics, they replaced the battery control module (thankfuly under warranty 15 miles before 50K miles!).

The second time, I figured that the carwash had something to do with it, because it only happened at that time (it does not rain here often). I was able to find the leak and fix it, took a blowdryer for 30 minutes to it and then took it to an independent and they cleared the codes, and no problems since.

Make sure you check that those gromets are properly placed, otherwise it will happen again.

 

It was the front SAM unit under the bonnet / hood. Basically the fuse box sits right underneath the engine vent holes - (Clever idea that one). As it was absolutley chucking it down (I do live in england ) on the day i had the failiure, i came to the conclusion that because the cover wasn't seated properly on the fuse box, water had got in and contaminated the SAM unit.


Haven't had any problems at the rear of the car yet although one of our directors has the e220 on a 04 plate and he has water swishing round the inside of his boot lid !

Thanks again everone for the input. This place is priceless