Newbie advice please....1993 CL500

[cockyapple]

Hello,

I have been offered a 1993 cl500 74,000 FSH in Silver for 6000......everything seems to work correctly........someone mentioned the `organic wiring` could be a problem with this age and model.........can anyone give me some advice or tips and comment on the price the car is being offered at ???????


cheers steve

 

[pascal]

Cockyapple,
Welcome to the site

I presume you mean a S500 Coupe (W140 coupe)
It seems on the lower side of the money okay, but only if it's as good as you say & has a genuine FSH & genuine mileage.

I would scrutinize the records firstly (Mot mileage matching service receipts)

I would also get it checked out by someone who is well up in these very complex motors.

I don't think that this car has biodegradable wiring

Also bear in mind that there is not a large market for these big coupes & that if things do go wrong they will be costly, and this is reflected in the price. They were very expensive new & a lot of car for your money.

I have seen one similar in Glasgow on 'Kennedy Cars' website for £7,000, but maybe this is the same one (reduced to sell). http://www.kennedycars.co.uk/_kennedycars.htm

PS the site didn't mention service record

 

[mjtray]

Steve,

You need to check whether the wiring harness has been replaced or whether it's on its way out......on this low mileage car, I assume that it won't have. If the check engine light comes on or refuses to go away, its a classic sign.

Yes, it was made of some bio-degradable insulation.....which bio-degrades too quickly, especially with the under body heat of the 5.0.

When it goes, most people just opt for a replacement harness at a cost of @£1000. The problem is that when the harness goes and its not caught in time it can cause glitches in the rest of the electrical systems, especially the ECU, which will then manifest themselves in odd electrical activity and rough running.

The most expensive and proper fix is to replace, harness, coil packs, leads and ECU......cost £2900......not surprisingly most people opt for the cheaper option and hope that they catch the problem in time.

The replacement harnesses by the way have a better insulation that avoids it degrading like the original.

Gearboxes on these cars can also be suspect if its a 5 speeder, which I assume it will be. Once past 120k they can play up, especially if the box has not had specified oil changes....rebuild roughly £1200

 

[CL500 Londoner]

Sorry to bring up an old thread but I need big help. I have always owned BMW's and never had a problem but I felt they had dropped in quality so I switched to mercedes 3 years ago when I purchased a 1997 CL500.

About 6 months ago the ABS and ESP light both came on and would never go out, Mercedes charged me £200 to diagnose it and they said it need an ABS sensor which is almost £2,000 fitted. I paid the £200 and took the car elsewhere with the new part and they fitted it at total cost £800. The problem persisted, I lost my patience and decided to give the car to Mercedes to diagnose again at another £200, they then reported that they have not got a clue where the fault is but to proiceed they will want £2,000 to change the ABS sensor AGAIN and that their only plan is to keep changing things until its fixed. Could this be connected to the organic wiring problem? Are there any tests I can do myself to check whether its due to this? If Mercedes are admitting they dont know the fault, what are my powers? Surely they arent allowed to just say that?

Other smaller problems are self closers that sometimes close, rear headrests that sound like they are gonna explode, rear heated screen button that wont switch off, my rear heated screen has been on for 6 months!!! They have had my car for 3 months and when I complain they say the delay was that they had trouble taking the wheels off.

 

[guydewdney]

JEEEEEZ!

Sounds like you are being taken for a ride mate.

Take to any decent indy with a STAR diagnostic. It takes about 5 minutes to do a full diagnostic, and get all the fault codes out.

First thing I woudl do - unplug the fuse for the rear heated screen. Now! It will start to over heat the wiring after a while and then you will have real problems...

Second. Unplug the fuse for the ABS, leave 5 mins. Plug back in. start engine. go from lock to lock on the steering. dive 100 feet. does the light go out?

If above fails, repeat - but undo battery negative lead instead of fuse.

The 1997 CL doesnt have the organic wiring issue.

BTW - on the star diagnostic system, you can call up a screen to see 'actual values' on the ABS sensors - so you can spin each wheel and see the signal come through to the computer. If one gives a signifiucantly different signal, its duff. (or the 'cog' it sits next to is full of crud)... Take all the wheels off, you will see a small tube (lipstick / clipper lighter sized) with a wire coming from it. close to the disc brake. check the 'cog' is clean. check the sensor is close (1mm? 2mm?) to the cog.

self closers - more info please - how what when?

rear headrests - do they make a 'donk donk donk' noise when they get tot he top / bottom? yes = replacement (mercman sells the motors for 50 quid iirc - I had to do one of mine)

HTH

Guy

 

[CL500 Londoner]

Guy, you are finally a man that has some answers.

I should have asked you before I gave the car in at Mercedes, now the car is with them and so I cant try any of this.

The self closers are not a massive worry but sometimes the door just wont self close but a good slamm will sort it but the bootlid sometimes goes through phases where it wont draw the chrome handle in.

I must also make it clear that this is my second car and sometimes its many weeks in between drives.

With regard to the headrests, you really have hit the nail on the head with your description. Does each headrest have its own motor or do they share one. Reason I ask is because if they have one each its a bit too coincidental that they both went isnst it? Besides, the motor part seems to be doing the job, its just that horrible noise, are you positive that its not a relay or something.?

And finally, please tell me who is the very best indy with all the diagnoistic stuff, preferably in North London, I want the the place that has the most experience with this model. Whats the number for this George Fraser, is that the name of the garage?

I really have had about as much as I can take with the car, I wanna push it into the Thames.

Thanks for your help

Chris

 

[CL500 Londoner]

First thing I woudl do - unplug the fuse for the rear heated screen. Now! It will start to over heat the wiring after a while and then you will have real problems...

Oh yes, I forgot to mention, Mercedes say the heated screen switch stays on because I have the wrong console and thhat the console on my car is from an E-Class. I asked them how come its worked for 3 years and they said its impossible. Another 5 Mercedes dealers said thats impossible as the console of different Mercs just dont fit eachother. Its beyond a joke.

 

[guydewdney]

there is no way in hell an E class console would fit an S class.

I have just checked the parts catalogue - the 'console' is totally different.

circuit diagram for the rear heated screen:-
http://www.autolib.diakom.ru:8001/CAR/Mercedes-Benz/1997/S420/SYSTEM WIRING DIAGRAMS/6362.pdf

note - it uses the 'combination relay' - this is a known issue with this car. its probably this.

check all the earthing points - heres the full list of the circuits (ok its for an S class, so just ignore some of the door bits )

http://www.autolib.diakom.ru:8001/CAR/Mercedes-Benz/1997/S500/SYSTEM WIRING DIAGRAMS/

Rear headrests - they are a self contained module, each headrest has its own motor, and a sensor that stops it when it reaches the end. diagram here:- http://www.autolib.diakom.ru:8001/CAR/Mercedes-Benz/1997/S500/SYSTEM WIRING DIAGRAMS/6450.pdf

actually - that might be a lie. BUT - i had exactly that problem, and replaced (one) of the headrests, and it was / is fine.

George Fraser is 0208 795 1055 - tell him Guy sent you along (Green CL 420)
warning - George is VERY busy, and if he says 'pick it up at 4' he means 6... LOL....

 

[CL500 Londoner]

The car was delivered back to me today after all this time and the service manager says nothing has been fixed as we cannot take the wheel off as its on too tight and they are worried that it may break of they force it. Furthemore the £2,000 ABS valve needs to be ordered from Germany and they want me to pay for this in advance. They apologised and returned the car. As soon as I got home I took a wrench to the front wheels and removed the front wheels by hand. I really give up with Mercedes, I really do. From day one they have been reluctant to deal with this car, as soon as they realised it was more than 10 minutes work they have been begging to bring the car back "at no charge sir". They have given me an Estimate for £3,000 for parts that may or may not solve the ABS mystery.

Do I accept? They have made it clear that they do not know the problem and that after I spend the £3k it may be in the same state.

 

[CL500 Londoner]

First thing I woudl do - unplug the fuse for the rear heated screen. Now! It will start to over heat the wiring after a while and then you will have real problems...

Second. Unplug the fuse for the ABS, leave 5 mins. Plug back in. start engine. go from lock to lock on the steering. dive 100 feet. does the light go out?

Hi Guy,

Today I tried to take your advice. Firstly, there is no ABS fuse, neither under the bonnet ahead of the driver or in the boot. Are there any other places where there are fuses????

Secondly, I was about to remove the fuse for the heated rear screen from the fuse place in the boot, while I was there with a tester, I realised that there are no live fuses there. And evidently so, tonight I drove the car and the rear heated screen button was stuck on (little LED illuminated) as usual but the rear screen was not actually being heated at all. Its really strange because its the rear fuses that feed the front fuses. I am so confused!!!!!!!

 

[guydewdney]

fuse 17 (boot) should be 'hot at all times' - check the PDF listing above under defogger circuit.

its a big one - 40 amp job.

fuse feeds relay, relay feeds screen. relay powered by control box in dash...

maybe:-
1) that fuse should be live, and it isnt.
2) the rrelay is dead?
3) the lighti is on as a sort of warning?

Theres an onboard diagnostic for the a/c control box. see here:-

http://www.continentalimports.com/ser_ic40142.html

or read below:--


The procedures for pulling Fault Codes go like this (See Chart 3): Turn on the ignition, and set the left temperature to "HI" and the right temperature to "LO." Then, simultaneously press buttons "Rest" and "EC" for five or more seconds. All of this must be done within 20 seconds. The "Recirculate" button will flash its LED. The screen will then go blank, and the first code can be brought up by pressing the right "AUTO" button.

Subsequent codes are retrieved by additional application of the right "AUTO" button. Figure 2 shows code B1234. Note that the code starts with "E" for error. Also note that the B1234 code appears as Eb1 234 on the screen.

The Individual Flap Tests are run by idling the engine, pressing the left and right "AUTO" buttons, setting temperatures to 72°, manually opening the fascia vents, and simultaneously pressing the "Rest" and "Recirculate" buttons for more than five seconds. The first step: Left display "0" and right display "LO" should appear. Pressing the left "AUTO" button changes the steps. Pressing the right "AUTO" button varies the two modes "HI" and "LO" for each step.


The functions that are checked are described in Chart 2 and can be verified by the actual air flow changes enacted. Figure 3 shows the third step (DTC) with "2" indicated on the left side and the "HI" mode indicated on the right.

All of these tests are so easy to run that they should be done frequently to gain familiarity with them. They definitely should be run before and after major dash surgery.

 

[CL500 Londoner]

fuse 17 (boot) should be 'hot at all times' - check the PDF listing above under defogger circuit.

its a big one - 40 amp job.

fuse feeds relay, relay feeds screen. relay powered by control box in dash...

maybe:-
1) that fuse should be live, and it isnt.
2) the rrelay is dead?
3) the lighti is on as a sort of warning?

Hi Guy, that entire link refers to aircon related stuff, none of it has to do with the rear heated screen. This morning I had another go, th rear heated screen light was on while I pulled out the actual fuse and it stayed on, is this possible?

Where are the relays and where in the dash is this control box?
Surely disconnecting the battery and reconnecting should switch off the rear heated screen, it doesnt, my feeling is its the switch itself is internall jammed on maybe.

 

[guydewdney]

The aircon computer / control unit incorperates the switch for the rear heated screen...

See if the aircon computer / unit has any faults in it.

Unless you have a totally different system???

 

[CL500 Londoner]

The aircon computer / control unit incorperates the switch for the rear heated screen...

See if the aircon computer / unit has any faults in it.

Unless you have a totally different system???

Aircon has no errors, its all fine. I diconnected the battery for a few hours and then reconnected it and the red light on the heated screen button was on again. (but not necessarily heating the screen!!!). The test thing you posted will not show any errors for the rear heated screen anyway. I have ordered the keys that remove the unit to test the switch itself as I am running out of ideas.

The ABS and ESP lights remain on, they illuminate after 10ft of driving and there seems to be nothing to stop them doing so. I tried all the advice of lock to lock and all that but nothing seems to work. Anymore suggestions?

PS, Where are the relays on this car and how can I test them?

 

[guydewdney]

ABS - silly thing to check - tyre pressures / sizes? the standard size for a CL500 is 255/45/18.

The next thing with the ABS is get the codes read, then you have a fighting chance.

Relay location. Sorry - no idea on the rear screen one.

Haver you actually run the test on the unit? If not - why not? OK - its the aircon system, but the switch is incorperated in it, and thus is part of it....

I would guess the relay would be in the boot, near the fuse box... pull the carpet back, theres loads of wires in there IIRC.



edit:-

found it:-
http://pages.prodigy.net/jforgione/MB_CF.html

 

[CL500 Londoner]

Haver you actually run the test on the unit? If not - why not? OK - its the aircon system, but the switch is incorperated in it, and thus is part of it....

Yes, No faults.

 

[CL500 Londoner]

New problem:

Since disconnecting the battery in an attempt to solve some electrical problems, the stereo is now asking for the code which I dont have. Just goes from bad to worse.

 

[Bolide]

Stereo / electrical problems

If it's a factory stereo the dealer can give you code from the VIN number

Why don't you get an expert to look at the car? It sounds like you've got more than one electronic problem and only a methodical approach from someone with experience will solve it all

In my experience with electronics the really confusing problems that seem to defy logic are caused by two (or more) simultaneous faults. This is why fault-finding is tricky and occasionally counter-intuitive


Nick Froome
www.w124.co.uk

 

[CL500 Londoner]

Never fear, I solved all my problems today. I part echanged the car for £10,000 and took a 1998 Bentley Arnage Twin Turbo.

I apologise in advance for what I am about to say but the CL was a great looker but was a terrible excuse for a vehicle. Electric headrests and self closing doors are not what make a car. I rate the CL very highly on gimmicks and style but the car is so unwilling to change direction at anything more than snails pace. The Bentley weighs loads more and drives so much nicer like a 5-series. The CL will be missed but the Mercedes main dealer service was the icing on the cake. I was appalled. It will be a long time before I buy any mercedes above an E-class. I sound like my dad now, but they don't make em like they used to.

THE END