undervoltage light and battery/alternator light
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c230 kopressor
undervoltage light and battery/alternator light
I've had my c230 kopressor for 2 1/2 years and has been running fine until yesterday. 
First the undervoltage light came on and then the battery/alternator light came on. Before I could take it in, it died and the battery wouldn't charge. I'm thinking it is either the voltage regulator or the alternator. Has anyone had this problem? Weird thing is, all this happened after I plugged my new ipod touch in my car.
First the undervoltage light came on and then the battery/alternator light came on. Before I could take it in, it died and the battery wouldn't charge. I'm thinking it is either the voltage regulator or the alternator. Has anyone had this problem? Weird thing is, all this happened after I plugged my new ipod touch in my car.
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mine was the voltage regulator which replace easy but if the car died then i think it was your alternator. if the lights get brighter when you press on the gas to 2000 rpm and dim at a light its most probably the regulator since current is comming out of the alt.
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c230 kopressor
voltage regulator
Well I will be finding out today as I have to get my car towed to a mechanic. I really hope it is the voltage regulator...a lot cheaper!!! All I know is everyone says not to go to the dealership as they cost way more! I love my benz but it seems that lots of people with the c class has had this same problem. Thanks for the reply back!!
I really hope it is the voltage regulator...a lot cheaper!!! All I know is everyone says not to go to the dealership as they cost way more! I love my benz but it seems that lots of people with the c class has had this same problem. Thanks for the reply back!!
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c230 kopressor
price
I thought it cost a lot since I found some online for 60 bucks. They charged me 100 bucks for regulator and 150 for labor....and 60 or 65 for diagnosis. I didn't go to the dealership 'cause it has always cost me LOTS more than other places.
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From: SCV SoCal
2002 CLK430
I don't know UK prices or if it differs for a C230, but a voltage regulator for a US spec 2002 CLK430 is part number 0031545106. At the dealer, it retails for $38. $26 at Autohaus AZ. It's secured to the rear of the alternator by two screws.
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c230 kopressor
:( terrible
Finally got my car back after having a new voltage regulator put in....and now some other stuff is not working!!!! My sunroof wont open, driver window doesn't work right and this srs light came on and said to visit workshop. The place that worked on it told me "they didn't touch anything else." I have no clue what's going on and will take it some where else.
My sunroof wont open, driver window doesn't work right and this srs light came on and said to visit workshop. The place that worked on it told me "they didn't touch anything else." I have no clue what's going on and will take it some where else.
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From: San Antonio, Tx
2000 CLK430
The shop is not lying...anytime that the car loses power or the battery is disconnected you have to do a manual reset on the windows and sunroof.
Do a search on this forum for the reset, there is nothing wrong with the car. It is a normal procedure that must be done when the car loses power.
Greg
Do a search on this forum for the reset, there is nothing wrong with the car. It is a normal procedure that must be done when the car loses power.
Greg
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c230 kopressor
Thanks egory13lil
That makes sense. I am a girl and know nothing about cars!! Still confused why the srs light would come on telling me to visit workshop. I really don't want to spend way more money by going to the dealer but thinking maybe I should? Otherwise, a friend referred me to a mechanic that works on foreign cars. I love my benz and I know its a great car, but it frustrates me dealing with all the mechanical stuff!!
That makes sense. I am a girl and know nothing about cars!! Still confused why the srs light would come on telling me to visit workshop. I really don't want to spend way more money by going to the dealer but thinking maybe I should? Otherwise, a friend referred me to a mechanic that works on foreign cars. I love my benz and I know its a great car, but it frustrates me dealing with all the mechanical stuff!!
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From: SCV SoCal
2002 CLK430
Calibrate your ABS and ESP systems by turning the steering wheel all the way to your RIGHT and then all the way to your LEFT. Then bring it back to the middle. The SRS and ABS lights should turn off.
If you have one-touch windows, push the right window switch all the way down and hold it until the right window is all the way down. Then push the switch, hold it, and raise the window all the way up. Do the same thing for the left window. Now your windows are set.
If you have a one touch sunroof, press the button to open, and hold it until the roof is fully open. Now close it. The roof is set.
Without sitting in it, move the driver’s seat all the way forward. Now move it all the way back. Do the same for the passenger seat. The seats are set.
Turn on your stereo and enter your radio code. If you don’t have the code, you can forget about listening to the radio until you get it. The dealer can give you the code for free.
If you have one-touch windows, push the right window switch all the way down and hold it until the right window is all the way down. Then push the switch, hold it, and raise the window all the way up. Do the same thing for the left window. Now your windows are set.
If you have a one touch sunroof, press the button to open, and hold it until the roof is fully open. Now close it. The roof is set.
Without sitting in it, move the driver’s seat all the way forward. Now move it all the way back. Do the same for the passenger seat. The seats are set.
Turn on your stereo and enter your radio code. If you don’t have the code, you can forget about listening to the radio until you get it. The dealer can give you the code for free.
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c230 kopressor
Calibrate your ABS and ESP systems by turning the steering wheel all the way to your RIGHT and then all the way to your LEFT. Then bring it back to the middle. The SRS and ABS lights should turn off.
If you have one-touch windows, push the right window switch all the way down and hold it until the right window is all the way down. Then push the switch, hold it, and raise the window all the way up. Do the same thing for the left window. Now your windows are set.
If you have a one touch sunroof, press the button to open, and hold it until the roof is fully open. Now close it. The roof is set.
Without sitting in it, move the driver’s seat all the way forward. Now move it all the way back. Do the same for the passenger seat. The seats are set.
Turn on your stereo and enter your radio code. If you don’t have the code, you can forget about listening to the radio until you get it. The dealer can give you the code for free.
If you have one-touch windows, push the right window switch all the way down and hold it until the right window is all the way down. Then push the switch, hold it, and raise the window all the way up. Do the same thing for the left window. Now your windows are set.
If you have a one touch sunroof, press the button to open, and hold it until the roof is fully open. Now close it. The roof is set.
Without sitting in it, move the driver’s seat all the way forward. Now move it all the way back. Do the same for the passenger seat. The seats are set.
Turn on your stereo and enter your radio code. If you don’t have the code, you can forget about listening to the radio until you get it. The dealer can give you the code for free.
To turn the srs light off by turning the steering wheel...does the car need to be on? My seats are okay 'cause they are not electric. My radio is working fine so don't think that needs reset...unless that has something to do with the other problems?
My passenger side window is working fine. The only problem besides the srs light- driver side window rolls down fine but does not roll up automatically when pressing up button once...and so I have to hold the button up to roll up...shade for the sunroof is also supposed to open automatically but I have to hold the button to get it open..and then when the shade is open, the sunroof window will not open at all.
I just think it is weird that only driver side and sunroof are affected.
Thanks for your help!!! 
Member
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From: Va
Supercharged CLK430 street/show car
Dont mean to thread jack but somewhat on topic
I have a question Marcus,
I got a custom 200 amp alternator built for my stereo and neon lights. Is the voltage regulator internal or external and do i need to make some modifications to the regulator to actually benefit from the added amps?
Thanks
I got a custom 200 amp alternator built for my stereo and neon lights. Is the voltage regulator internal or external and do i need to make some modifications to the regulator to actually benefit from the added amps?
Thanks
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LET C32 2002
Is there a website I can order a valeo regulator for my valeo alternator?
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From: SCV SoCal
2002 CLK430
Benz-C230: yes, the engine should be running.
Nasty: I PM'd you.
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LET C32 2002
I decided to switch to Bosch alt since its available today and maybe I can get it running today its been in garage a week a fellow forum member locally has done it.
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2002 C230 Coupe
I got this same message yesterday. I got in my car,started the engine and as I started to move in reverse I heard this crunching (or arcing) noise. Up popped the message. Turned it off and started again. Same message again. Car starts and runs fine. I don't drive it much so I haven't looked into it yet.
Thread Starter
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c230 kopressor
I got this same message yesterday. I got in my car,started the engine and as I started to move in reverse I heard this crunching (or arcing) noise. Up popped the message. Turned it off and started again. Same message again. Car starts and runs fine. I don't drive it much so I haven't looked into it yet.
All I needed was a new voltage regulator which was good 'cause it could have been the alternator and that would have sucked!!
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Merc clk 230 kompressor cabriolet
Hi, I hope you can help,I have a 2002 clk 230 kompressor cab, I started getting battery/alternator visit workshop warning message flash up with a picture of a battery about 5 months ago. I had a merc specialist take a look and he had alt rebuilt and the message went for a couple of months. Then the stereo starting losing volume about the same time the error message came back. I sent it back and they re repaired alt. picked it up tonite,got 3 miles down road and message came back up. Anyone got any suggestions please?
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Joined: Jun 2013
Posts: 287
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From: New Hampshire
Magma Red W208 55 AMG, W203 C230 Kompressor Sedan 6speed M/T, W220 S500
Hi, I hope you can help,I have a 2002 clk 230 kompressor cab, I started getting battery/alternator visit workshop warning message flash up with a picture of a battery about 5 months ago. I had a merc specialist take a look and he had alt rebuilt and the message went for a couple of months. Then the stereo starting losing volume about the same time the error message came back. I sent it back and they re repaired alt. picked it up tonite,got 3 miles down road and message came back up. Anyone got any suggestions please?
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LET C32 2002
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From: SCV SoCal
2002 CLK430
The voltage regulator is a separate, normal wear, part. The last one I bought cost $25. Once you replace one, it's obvious why it's considered "normal wear". Here's a DIY link
