s600 w140 coupe electrical faults

[bouzirouge]

hi one and all. i'm in the process of buying one of these supercars. i know about the biodegradeable harness problems with the earlier ones. can anyone tell me if the indicators and wipers being on all the time is engine bay or cabin harness related? if engine bay, i'll replace it and be over the moon. if cabin, i'll have to think carefully that i have enough time for the job as it's such a huge undertaking.

the car's a uk model '94 with full uk mb service history. it's not been diagnosed by the dealer yet. i'm based in rural sw france so dealers are not exactly thick on the ground. of course if it was just the switchgear!!!! wishfull thinking i'm sure. mileage is 140,000miles, though if it sait 14,000 on the clock it would seem real. no signs of interior wear, blemishes on the paint etc. when they built these they must have had a long life planned. what were they thinking with the biodegradeable insulation?

any helpfull pointers or info will add to my limited knowlege so don't be shy.

 

[jibcl500]

Without researching I think its the multifunction relay in the front fuse box at fault, cant remember the part number but from memory you cant buy them anymore.
Relay should be fixable.

Carl www.w140.co.uk is a good chap for parts.

jib

 

[television]

You have the N10 in that car, the same as some other models, it maybe fixable but worth cleaning the fuse holders, if both have failed then possible stalk fault

 

[mikestrivens]

As above, these are wonderful cars and I love mine. The drive is superb, though the fuel consumption is pretty dire.

 

[bouzirouge]

hi guys, thanks for sharing your knowledge. the fuses are ok. in fact the only way i can drive the car is if i pull the indicator and wiper fuses. that's the only way to turn them off. i'll be over the moon if it's not the harness.

ebay has several switch and relay units at what seems huge cost for what they are, but still nothing compared to replacing the body harness so i'll be delighted to get one of these. what can i check to find out which unit is faulty? the fault started as l/h indicators on all the time, now it's wipers too.

i've not picked the car up yet so i can't tell you more than that at the moment. is it safe enough to pull both fuses to collect (drive) it? i did lots of reading before i went to see the car. i'm starting to think i've jumped to the wrong conclusion having read of the harness horrors. i spent a couple of hours looking it over and that's the only thing i can find wrong with the car.

the car has been parked in a barn for several years since the fault appeared so i think dirty contacts etc not the problem. i'm ok at electrical fault finding and i'm sure in a few months of ownership i'll be quite familliar with it. such a help to be pointed in the right direction.

regards, stewart

 

[television]

Its all in that N10 relay, indicators and wipers and heated rear window

 

[bouzirouge]

hi, available now on ebay uk, wiper switch is £58 delivered. this relay, correct one? doesnt say n10?? part no 1408203026, is £127.50 delivered. so much better than a harness, but which one to get. how do i test these parts? regards, stewart

 

[television]

No the N10 is a relay that is in a front relay box

 

[bouzirouge]

hi guys, so if i understand it right the n10 is a relay from around the fuse box in the front? is that under the bonnet or inside the car? does this relay say
N10 on it anywhere? on ebay there are two relays listed as wiper. i've included links to both. won't bore anyone with the link to the control switch. any idea which one i want and where it comes from? i want to make sure i'm looking/testing/buying the right bit.

http://www.ebay.co.uk/itm/150762288173?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

http://www.ebay.co.uk/itm/200799958700?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

i'm going over to have another look at the car tomorrow. i'll do my best to locate the parts unless i need to dismantle something first. i'll take some pics. any thoughts on anything else i should check over? any special pics i can take to help anyone else or to identify bits? regards, stewart

 

[television]

These are the only part numbers that I have, I cannot guarantee this is the problem

A 140 820 30 26 CONTROL UNIT
Replaced_By: A 140 820 13 26 -
A 140 820 13 26 CONTROL UNIT
BLINKER/HAZARD-WARNG.-L.SENDER UNITS, HEATED REAR PANE,WIPER,TRAILER COUPL. [851]

A 140 820 71 26 CONTROL UNIT
BLINKER/HAZARD-WARNG.-L.SENDER UNITS, WIPER,TRAILER COUPLING

 

[bouzirouge]

hi guys, see pics of my new car once i've worked out how to re-size them. dug it out of the barn today, had to move all the other mercedes out of the way first though. some really nice classics in there. the man has crates and crates of spares for these older cars. he's not a fan of new fangled types he says.

boy was i dissapointed when i got to drive it. in park or neuteral, lots of revs. sounds fantastic even though i'm sure there was the occasional missfire in there too. into gear and suddenly the throttle goes unresponsive. sluggish to rev and almost no go. out on the road, really slugguish but flies when you wait the few seconds it takes to kickdown. promising but on the way back from rest it couln't climb a gradient so slight i couldn't tell it was there. not slipping mind, just rev to 8 or9 hundred and stop like the brakes are on.

rained the whole time too so not really able to do much investigating. any ideas? no "brakes are jammed on" smell. fluid red, smells ok. is this likely to be electrical or mechanical? i'm not buying it just to break it up. i'm not a masochist! i'm really keen to close this deal but not if it means 10k of repairs just to get it on the road.

 

[television]

You need to take some one that knows them

 

[bouzirouge]

that would be a huge help. i'm handy with the spanners and with my trusty multimeter. but this is an altogether more complicated undertaking. can anyone recommend someone in the north dordogne of sw france? or even be specific about what i need in the way of code readers. obd1 or 2? any special softwear?

it's been parked since the indicators and wipers suddenly started to stay on all the time. i discovered yesterday the heated rear window is on all the time too so from previous posts that seems to point to the relay behind the fusebox under the bonnet. that was where i was going to start. the car was driven into the barn then and has been out on the road once since around 18 months ago. it drove fine at that point. so whatevers happened has happened whilst it was parked up. it's not had a battery in it for 18 months. that may be relevant?

i'm coming to the conclusion that this is all electrical and it's stopping the car from driving. gearbox seems to change with a thump but when it does and the rev's are high enough as a result it flies and seems normal. it feels like a range rover in limp home mode or a laguna or an alfa with a dodgy maf, all of which i've had in the past. whilst i was poking about at the fuse box i was able to see the old wiring looking to be in perfect condition. i looked very carefully. i'm starting to suspect it's already been changed. the central locking doesn't work either from the keu or the switch on the dash. fun and games putting petrol in. the seatbelt servants don't work and only one rear headrest moves. all else is working fine. apart from the rear view mirror that won't adjust up and down, only side to side.

help!!!!

 

[jibcl500]

that would be a huge help. i'm handy with the spanners and with my trusty multimeter. but this is an altogether more complicated undertaking. can anyone recommend someone in the north dordogne of sw france? or even be specific about what i need in the way of code readers. obd1 or 2? any special softwear?

it's been parked since the indicators and wipers suddenly started to stay on all the time. i discovered yesterday the heated rear window is on all the time too so from previous posts that seems to point to the relay behind the fusebox under the bonnet. that was where i was going to start. the car was driven into the barn then and has been out on the road once since around 18 months ago. it drove fine at that point. so whatevers happened has happened whilst it was parked up. it's not had a battery in it for 18 months. that may be relevant?

i'm coming to the conclusion that this is all electrical and it's stopping the car from driving. gearbox seems to change with a thump but when it does and the rev's are high enough as a result it flies and seems normal. it feels like a range rover in limp home mode or a laguna or an alfa with a dodgy maf, all of which i've had in the past. whilst i was poking about at the fuse box i was able to see the old wiring looking to be in perfect condition. i looked very carefully. i'm starting to suspect it's already been changed. the central locking doesn't work either from the keu or the switch on the dash. fun and games putting petrol in. the seatbelt servants don't work and only one rear headrest moves. all else is working fine. apart from the rear view mirror that won't adjust up and down, only side to side.

help!!!!

Are there any lights on the dash? Sounds like battery voltage is low.

jib

 

[shayes]

If its been parked up in a barn in SW France possibly an animal has had lunch on the wiring?

Or is it in UK?

So the faults are:
Rear window taking most power
hesitancy in acceleration
electrics like the car has a host polterguist

 

[shayes]

If you are searching for parts I would also consider ebay.com as the parts you get from Sunny California are likely to be better. I have bought several relays and still have some W126 Kickdowns to get rid of. No use for your car.

Also, if the car is in France and you have a problem thinking who can deal with this, I do know where there is a small garage where the owner seems to love these older Cars. I drive by it on occasions. Can't say if they can help or are competent, but you may want to check them out. I'll pm you if you are interested.

 

[bouzirouge]

Please pm me the details of the garage.
I took my brand new battery from my land rover over with me. it's not quite big enough at 760ah and 88a. according to the spec for these cl's that should be 1000 and 100. it was reading 13.8 volts before starting and a stable 14.4 once running, so i assumed that was enough.

My thoughts were to start by removing and cleaning up all the earth straps and replacing the window/indicator/heated rear window relay. Maybe a good clean up and scoot of wd40 for the fuses too?

Is there something else i should be looking at? I've already posted, with no reply as yet, as to what code reader, software and connectors i need for my '94 cl600, uk model. i think i'll get one if it's not rediculously expensive, as it appears one of these is going to be an essential part of the toolkit. With a code reader I should be on the way to at least having things to check and places to look. I see the code translator as a sticky, so i may not need help with the actual codes. I could well need help when deciding what to do about the potential faults though.

Please share all those little nuggets of information. You never know, it might just be the information I or someone else needs. I'm sure others read these posts too. I know i read masses of them trying to learn what i could before posting. All the best, Stewart

 

[shayes]

large place SW France- so maybe a lot further than you'd wish to go.

Its at a place called Lesterps and its on the D30 road to Confolens.

If you go onto Google Earth and put in Lesterps when you home in, to your left you find the D30 and if you travel along it a short way before you reach the D32 you can drop the man into the road where you see a car park area below the road and buildings the other side. Theres a W126 and possibly an E (don't think its wide enough for an S)class on forecourt. You can probably see the phone number - Hows your French?

 

[bouzirouge]

Hi, no warning lights on dash, no animals in this barn. i've maybe misdescribed it as a barn. it's more a museum to old mercs. you could eat you dinner from the floor. when i'm over tomorrow i'll ask if i can snap some of the others in there too. everything from concourse rebuilds to crates of new and unwrapped spares for his collection of old mercedes.

 

[shayes]

did you take out the fuse to the rear window heater to stop the drain?