C-Class (W203) 2001-2007, C160, C180, C200, C220, C230, C240, C270, C280, C300, C320, C230K, C350, Coupe

relay diagram for w203

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Old Dec 15, 2011 | 09:40 AM
  #26  
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C240, S500
2004 C240 No Lights

Wow, Glyn you just dropped my spirits. I was sure that I had found the culprit. Is there anyway I can have this switch checked for functionality other than plugging it into another C240?



Originally Posted by Glyn M Ruck
The C240 switch only lights the position markings in the two fog light positions. The 240 did not light a lot of dash functions such as the HVAC vent rollers. Only the C320 did. So this is not a measure of an operating switch I'm afraid. Sorry to be the bringer of bad news but I've just sold my C240 after 8 years of faultless service.
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Old Dec 15, 2011 | 02:22 PM
  #27  
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C240, S500
2004 C240 No Lights

Well, I am about out od DIY ideas. Will be taking the Benz to the shop on Monday to go on the STAR Diagnostics.
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Old Dec 15, 2011 | 03:37 PM
  #28  
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late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I'm really sorry to disappoint you but better than chasing down ghosts. I don't have the pin measurements on the switch. Better to get her on a Star. Then you will know where you stand. Depending on what they find you may be able to find used components. The switch assembly on later cars was not colour coordinated but black for German build. For your sake I hope it is the switch.

EDIT: Please request a copy of the Star findings. You will be paying for it.

Last edited by Glyn M Ruck; Dec 15, 2011 at 03:39 PM.
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Old Jan 14, 2012 | 02:30 PM
  #29  
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C240, S500
C240 No Lights

Hello Glyn and Moviela,

I just wanted to follow-up and thank you for your assistance.

I had parked the car in the garage and avoided it for awhile, but the wife was not happy.

I am glad to announce that I have "Lights"!!

It was the swithch after all. I took it to a dealer that works exclusively with MB's and had the Star capapbilities. After he checked all codes, and there were a few sicne I had disconnected the battery he noticed the the switch was a salvage part which I also noticed. There was a pin or two broken in the switch and he ordered a new one. We now have lights!! and the wife is happy, which makes me happy.

Thhanks again for all the help.
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Old Jan 14, 2012 | 05:13 PM
  #30  
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late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
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Old Nov 4, 2014 | 09:58 AM
  #31  
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C320
turn signals, wipers, horm and the instrumental cluster not working properly

-------------------

Hi

I have a C320 2001 and it has problems with the turn signals, wipers, horm and the instrumental cluster not working properly. They worked intermittenly. I can not change the function on the cluster. The cluster also shows error of tail lights "bring car to shop" but both are working good. I checked the fuses and they are OK. Replaced the front SAM unit but the problems could not be fixed. Does anyone have any suggestions? The car is running good except these problems.

Thanks.

Last edited by babenzforum; Nov 4, 2014 at 10:01 AM.
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Old Nov 5, 2014 | 11:06 AM
  #32  
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C320
Hi. I have a C320 2001 and its signal lights, wiper, horn do not work and the instrumental cluster fructions cannot not be changed. I thought there was problem with the front SAM but it was not because I replaced the front SAM and the problems still there. Can you give any suggestions?

how about the rear SAM problem? Any idea?

Thanks
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Old Nov 5, 2014 | 11:42 AM
  #33  
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2002 C230 Coupe
Originally Posted by babenzforum
Hi. I have a C320 2001 and its signal lights, wiper, horn do not work and the instrumental cluster fructions cannot not be changed. I thought there was problem with the front SAM but it was not because I replaced the front SAM and the problems still there. Can you give any suggestions?

how about the rear SAM problem? Any idea?

Thanks
All that stuff has to go down the steering column wiring harness. You might get lucky and get it to clear up just by unplugging and reconnecting old connectors, like I did on my light switch. Horn and cluster functions have to go through the clockspring, but not the turn signals and wipers, so look for connection at the base of the steering column.
Electrical gremlins are PITA even in cars without CANbus. We can tra a couple simple things - then it's off to STAR diagnostics. Lots of luck with it.
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Old Nov 5, 2014 | 11:45 AM
  #34  
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Your tail lights might be running on their spare lamps. Check this.

It sounds as though you have a cluster or CANbus problem. You need to get this car onto a Star for a full diagnosis. You say you changed the front SAM. Who reprogrammed it for you?

Cluster & CANbus problems are not DIY unless you have your own Star.
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Old Nov 5, 2014 | 12:05 PM
  #35  
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C320
Originally Posted by Glyn M Ruck
Your tail lights might be running on their spare lamps. Check this.

It sounds as though you have a cluster or CANbus problem. You need to get this car onto a Star for a full diagnosis. You say you changed the front SAM. Who reprogrammed it for you?

Cluster & CANbus problems are not DIY unless you have your own Star.
Thak you guys very much. I will check as your suggestions.
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Old Nov 5, 2014 | 12:13 PM
  #36  
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I hope it's just an intermittent CANbus short or loose connection on the bus. New clusters are expensive.
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Old Nov 5, 2014 | 12:55 PM
  #37  
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C320
Originally Posted by Glyn M Ruck
I hope it's just an intermittent CANbus short or loose connection on the bus. New clusters are expensive.
Thanks Glyn. I also guessed that. Do you know where the CANbus I can check by myself?
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Old Nov 5, 2014 | 05:26 PM
  #38  
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
You would have to pull half the car apart to check CAN networks without a Star. There is a basic 3.7 MB W203 CAN network pdf. in the Wiki that I posted there that will help you understand the magnitude of what you are trying to take on.

Wiki access is messing around at present. Will try & have fixed.
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Old Dec 14, 2014 | 12:50 PM
  #39  
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2004 C32, 2006 Honda CBR1000RR, 2007 Harley NightRod, 2013 Harley Road Glide Custom
Question

I know this is an old post and thanks sharing. I need to check the seat heater fuses. I found the fuse box in the trunk and under the hood, but can't find the one near the driver's door. What am I missing? Thanks.

Bob



Originally Posted by Glyn M Ruck
If you have all lights out it is most likely the SAM's = Signal Acquisition & Activation Module. They operate off of the respective CANBUS so that you don't have thousands of wires running all over the car.

You have 3 fuse points in a W203. Driver's side of dash. In the front SAM & in the rear SAM. Your fuse etc. diagram s/b in the driver's side of dash fusebox.

You have one SAM in the rear engine compartment opposite side to the battery under a little water cover with twist fasteners & then under a cover with lever snap fasteners. The rear SAM is in the trunk on the LHS under a cover in the trunk lining.

Light activation is by the SAM's themselves when they receive a signal on the CANBUS. They are electronically protected - no fuses.

I hope you don't have blown SAM's as they are expensive. Lets hope they just need reprogramming or similar.



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Old Dec 14, 2014 | 08:37 PM
  #40  
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2002 C230 Coupe
There's a cover in the end of the dash, that's only visible when the driver's door is open.
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Old Dec 15, 2014 | 08:56 AM
  #41  
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Old Dec 15, 2014 | 02:40 PM
  #42  
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Originally Posted by KSKarl
There's a cover in the end of the dash, that's only visible when the driver's door is open.
Thanks!
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Old Dec 15, 2014 | 02:41 PM
  #43  
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Originally Posted by Glyn M Ruck
Thank you. Excellent shot of it.

Bob
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Old Dec 15, 2014 | 07:06 PM
  #44  
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It turns out fuses 25/41 are fine. So, my problem must be the switch or the element itself.
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Old Jan 26, 2015 | 04:22 PM
  #45  
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c200 and lr 90
starter relay

hi do you please know what part number or where i can purchase a starter relay for my 2002 c200 kompressor i cant seem to find 1
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Old Jan 26, 2015 | 06:20 PM
  #46  
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C230 COUPE 2003 M271
also, why do the low beams have fuses while all other exterior lights are electronically protected/controlled by SAM?
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Old Jan 27, 2015 | 03:57 AM
  #47  
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Originally Posted by wvadam
also, why do the low beams have fuses while all other exterior lights are electronically protected/controlled by SAM?
Only the small marker lamps are protected by a 7.5 A fuse. The headlights and fog lights in the front are controlled by a computer that is measuring the current flowing in the lamp circuit. If the current goes to high (like a short in the wiring) the computer just turns off the transistor that turns on the lamp.

Fuses are not needed with this arrangement. The measuring circuit not only allows protection of the wiring much faster than a fuse, it also allows a lamp out warning, and can sense over current conditions (like a failed lamp) that would not be protected by a fuse.
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Old Jan 27, 2015 | 04:02 AM
  #48  
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Originally Posted by green23
hi do you please know what part number or where i can purchase a starter relay for my 2002 c200 kompressor i cant seem to find 1
Consult Startek, or if outside the US, contact your dealer with the VIN to assure you are given the correct part number.

They rarely fail, are you sure it is not a bad starter solenoid or starter itself? Have you checked the heavy gauge wires to the starter for condition? The latter are more often pits in the path of progress for starter problems.
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Old Jan 27, 2015 | 04:04 PM
  #49  
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Originally Posted by Moviela
Only the small marker lamps are protected by a 7.5 A fuse. The headlights and fog lights in the front are controlled by a computer that is measuring the current flowing in the lamp circuit. If the current goes to high (like a short in the wiring) the computer just turns off the transistor that turns on the lamp.

Fuses are not needed with this arrangement. The measuring circuit not only allows protection of the wiring much faster than a fuse, it also allows a lamp out warning, and can sense over current conditions (like a failed lamp) that would not be protected by a fuse.
Interesting. So fuses 62,63 listed in the fuse diagram above as 'low beam' - is this not referring to the head lights?
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Old Jun 23, 2016 | 12:50 AM
  #50  
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mercedes c230
2002 mercedes c230 AC not cooling

Hello all,

I have 2002 c230 (w203) and had AC problem a few days ago, it started blowing hot air. I noticed that the fan is not working when AC is on. When I start the car and keep AC off, the fan spins slowly. When I turn AC on, it completely stops.

According to what I read above,
- fan control unit
- fan relay
- front sam
- or pressure sensor

might the cause for this problem. Is there any other possible reason? Can anyone explain how to identify or how to check what the cause of problem, with a language that someone like me who is not a mechanic can understand?

Also just noticed that viper is not working too. Is it about relay or anything else?

I appreciate if you can support your solutions with some pictures or diagrams.
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