Fog light/power mirror issues
#1
Fog light/power mirror issues
First I have searched and came up short, on my 01 C240. First issue is the power mirrors do not work, all fuses are good. Second issue is the front/rear fog lights don’t work with the switch along with the parking light setting. All lights but the fog lights turn on when the switch is turned to the all on position. I bought a used switch assembly off eBay and get the same results; so I can be pretty sure that rules the switch out. The weird thing with the front fog lights is when I exit the car the fog lights come on with the parking lights for the 30 seconds for the courtesy feature. Anyone have any guidance on where to go from here? Thank you in advance.
#2
MBWorld Fanatic!
Join Date: Dec 2003
Location: Vancouver, BC, Canada
Posts: 3,124
Likes: 0
Received 210 Likes
on
201 Posts
2003 C230K Coupe Orion Blue
Where are you located? Might want to put that into your signature. Tells the rest of us which version of the car you have.
The fogs are receiving power, so that rules out the wiring.
Are you pulling the switch (dial) after turning it to activate the front and rear fog lights? Bit of a dumb question but I have to ask. Pull out 1 click for front fogs, 2 clicks to also turn on the rear fog. Check the manual if you are unsure what I am talking about.
Lastly, the high beams and fogs cannot be operated at the same time. Are your high beams on?
The fogs are receiving power, so that rules out the wiring.
Are you pulling the switch (dial) after turning it to activate the front and rear fog lights? Bit of a dumb question but I have to ask. Pull out 1 click for front fogs, 2 clicks to also turn on the rear fog. Check the manual if you are unsure what I am talking about.
Lastly, the high beams and fogs cannot be operated at the same time. Are your high beams on?
#3
I am in Washington state USA AND ITS MY 2001 C240 sedan 6 speed manual.
yes I am pulling the switch. I appreciate the basics. And no the high beams are not on when I try; just the main beams.
yes I am pulling the switch. I appreciate the basics. And no the high beams are not on when I try; just the main beams.
Where are you located? Might want to put that into your signature. Tells the rest of us which version of the car you have.
The fogs are receiving power, so that rules out the wiring.
Are you pulling the switch (dial) after turning it to activate the front and rear fog lights? Bit of a dumb question but I have to ask. Pull out 1 click for front fogs, 2 clicks to also turn on the rear fog. Check the manual if you are unsure what I am talking about.
Lastly, the high beams and fogs cannot be operated at the same time. Are your high beams on?
The fogs are receiving power, so that rules out the wiring.
Are you pulling the switch (dial) after turning it to activate the front and rear fog lights? Bit of a dumb question but I have to ask. Pull out 1 click for front fogs, 2 clicks to also turn on the rear fog. Check the manual if you are unsure what I am talking about.
Lastly, the high beams and fogs cannot be operated at the same time. Are your high beams on?
#4
Super Member
I have two suggestions:
1. I had turn signal issues that were caused by a failed Front SAM (Signal Acquistion and Activation Module.) I don't know whether the Front SAM controls the fogs and mirrors, but you may want to search and see what you can find. This link provides the basic information.
2. I had problems with my lights and also bought a used switch from a "part out" to see whether that would cure it. It turned out that the used switch assembly was also defective. I bought a new switch which fixed the problem. The parts technician at the Mercedes dealer told me it was a common failure item. I don't think you can be 100% confident that your used switch is in good condition.
The common wisdom is that the electronic parts in the W203's (especially the pre-facelift cars like yours) are the cars' Achilles heel. I have installed several used electronic components on my car with good results. However, used electronic parts are a gamble. In addition to the headlight switch, the used Front SAM I installed failed after about a year.
1. I had turn signal issues that were caused by a failed Front SAM (Signal Acquistion and Activation Module.) I don't know whether the Front SAM controls the fogs and mirrors, but you may want to search and see what you can find. This link provides the basic information.
2. I had problems with my lights and also bought a used switch from a "part out" to see whether that would cure it. It turned out that the used switch assembly was also defective. I bought a new switch which fixed the problem. The parts technician at the Mercedes dealer told me it was a common failure item. I don't think you can be 100% confident that your used switch is in good condition.
The common wisdom is that the electronic parts in the W203's (especially the pre-facelift cars like yours) are the cars' Achilles heel. I have installed several used electronic components on my car with good results. However, used electronic parts are a gamble. In addition to the headlight switch, the used Front SAM I installed failed after about a year.
Last edited by KevinH2000; 12-24-2021 at 08:30 AM.
#5
I have two suggestions:
1. I had turn signal issues that were caused by a failed Front SAM (Signal Acquistion and Activation Module.) I don't know whether the Front SAM controls the fogs and mirrors, but you may want to search and see what you can find. This link provides the basic information.
I have read that link and I think that’s where my problems are. I am waiting for my scan tool to arrive today to see what I can find there. Otherwise all of your comments make a lot of sense.
2. I had problems with my lights and also bought a used switch from a "part out" to see whether that would cure it. It turned out that the used switch assembly was also defective. I bought a new switch which fixed the problem. The parts technician at the Mercedes dealer told me it was a common failure item. I don't think you can be 100% confident that your used switch is in good condition.
The common wisdom is that the electronic parts in the W203's (especially the pre-facelift cars like yours) are the cars' Achilles heel. I have installed several used electronic components on my car with good results. However, used electronic parts are a gamble. In addition to the headlight switch, the used Front SAM I installed failed after about a year.
1. I had turn signal issues that were caused by a failed Front SAM (Signal Acquistion and Activation Module.) I don't know whether the Front SAM controls the fogs and mirrors, but you may want to search and see what you can find. This link provides the basic information.
I have read that link and I think that’s where my problems are. I am waiting for my scan tool to arrive today to see what I can find there. Otherwise all of your comments make a lot of sense.
2. I had problems with my lights and also bought a used switch from a "part out" to see whether that would cure it. It turned out that the used switch assembly was also defective. I bought a new switch which fixed the problem. The parts technician at the Mercedes dealer told me it was a common failure item. I don't think you can be 100% confident that your used switch is in good condition.
The common wisdom is that the electronic parts in the W203's (especially the pre-facelift cars like yours) are the cars' Achilles heel. I have installed several used electronic components on my car with good results. However, used electronic parts are a gamble. In addition to the headlight switch, the used Front SAM I installed failed after about a year.
#6
Super Member
This thread shows the process I followed to determine the problem was the front SAM.
I tried several other options before deciding to replace the front SAM. I returned the new SAM I bought and was able to reprogram a used one. About a year later, the used SAM also failed. I decided I didn't want to keep replacing SAM's and installed a new one the second time.
I tried several other options before deciding to replace the front SAM. I returned the new SAM I bought and was able to reprogram a used one. About a year later, the used SAM also failed. I decided I didn't want to keep replacing SAM's and installed a new one the second time.
#7
I have two suggestions:
1. I had turn signal issues that were caused by a failed Front SAM (Signal Acquistion and Activation Module.) I don't know whether the Front SAM controls the fogs and mirrors, but you may want to search and see what you can find. This link provides the basic information.
2. I had problems with my lights and also bought a used switch from a "part out" to see whether that would cure it. It turned out that the used switch assembly was also defective. I bought a new switch which fixed the problem. The parts technician at the Mercedes dealer told me it was a common failure item. I don't think you can be 100% confident that your used switch is in good condition.
The common wisdom is that the electronic parts in the W203's (especially the pre-facelift cars like yours) are the cars' Achilles heel. I have installed several used electronic components on my car with good results. However, used electronic parts are a gamble. In addition to the headlight switch, the used Front SAM I installed failed after about a year.
1. I had turn signal issues that were caused by a failed Front SAM (Signal Acquistion and Activation Module.) I don't know whether the Front SAM controls the fogs and mirrors, but you may want to search and see what you can find. This link provides the basic information.
2. I had problems with my lights and also bought a used switch from a "part out" to see whether that would cure it. It turned out that the used switch assembly was also defective. I bought a new switch which fixed the problem. The parts technician at the Mercedes dealer told me it was a common failure item. I don't think you can be 100% confident that your used switch is in good condition.
The common wisdom is that the electronic parts in the W203's (especially the pre-facelift cars like yours) are the cars' Achilles heel. I have installed several used electronic components on my car with good results. However, used electronic parts are a gamble. In addition to the headlight switch, the used Front SAM I installed failed after about a year.
so I replaced the Seitch with a brand new one and have the same issues. Switch didn’t fix it. According to the codes they led me to the switch. Any other ideas?
![](https://cimg7.ibsrv.net/gimg/www.mbworld.org-vbulletin/2000x1504/8314c709_2068_4d46_9ff6_49d4cf7094d0_550eedc410b8a8d2b5284ec39d5023b352f44840.jpeg)
Trending Topics
#8
Super Member
Based on my experience it appears that the front SAM is the problem. When I ran into my problem with the lights I was concerned about “throwing parts at the problem.” Therefore I am reluctant to recommend that you buy a replacement SAM because it is an expensive part. It is also significantly more difficult to replace than the headlight switch. I don’t like gambling with my own money and I would not want you to throw money away based on my advice.
Before you replace the SAM, I suggest that you complete an extensive search on the problems caused by a defective front SAM to determine whether anyone else experienced the same problem and repaired it by replacing the SAM.
Another consideration when using my experience as a guide is that I have a “post facelift” W203. There may be differences between our cars that make my experience of questionable value as a source of information.
Before you replace the SAM, I suggest that you complete an extensive search on the problems caused by a defective front SAM to determine whether anyone else experienced the same problem and repaired it by replacing the SAM.
Another consideration when using my experience as a guide is that I have a “post facelift” W203. There may be differences between our cars that make my experience of questionable value as a source of information.
#9
MBWorld Fanatic!
Join Date: Dec 2003
Location: Vancouver, BC, Canada
Posts: 3,124
Likes: 0
Received 210 Likes
on
201 Posts
2003 C230K Coupe Orion Blue
I've been told that the front SAM can fry if people reconnect the negative wire before the positive after disconnecting the battery. Always reconnect positive first. Not sure if it applies to facelifted cars, but definitely applies to pre facelift.
Did you disconnect the battery at any point before the problems appeared?
Did you disconnect the battery at any point before the problems appeared?
#10
I've been told that the front SAM can fry if people reconnect the negative wire before the positive after disconnecting the battery. Always reconnect positive first. Not sure if it applies to facelifted cars, but definitely applies to pre facelift.
Did you disconnect the battery at any point before the problems appeared?
Did you disconnect the battery at any point before the problems appeared?