Quick Question On Bulbs ;) - Mercedes Benz SLK Forum

SLK R170 General Discussion SLK 200, SLK 230K, SLK 320, SLK32 AMG

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#1 Old 12-24-2016
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Quick Question On Bulbs ;)

Hi Guys

Thinking of upgrading the headlight bulbs (maybe rear too) on a year 2000 - 320 SLK

Am I right in thinking it's 2 x H7 and 2 x H4 (with 2 x T10 for side lights)

Just wanting to double check as I plan on LED for side lights, and Osram or Xtream Vision for head lights as replacements

Any issue's with dash warning lights when changing bulbs?

Thanks
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#2 Old 12-24-2016
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exterior bulbs must be canbus error free
interior are not except the inside trunk bulb

your owner's manual tells you what size

https://www.slkworld.com/slk-r170-gen...00-2004-a.html

https://www.slkworld.com/slk-r170-gen...ront-rear.html



What are CAN-bus Error Free LED bulbs?
CAN-bus Error Free LED bulbs are LED bulbs that have resistors that are internally/externally attached. European vehicles are the typical candidates for these types of LED bulbs as the electrical system on these European cars have sensors that detect whether the light is working or not. Since LED bulbs draw far less power than the stock filament bulbs, the vehicle’s computer may think that the bulb is out so it'll throw an "error message" or "bulb out" warning the driver that the light is out; thus the name "error free". The resistor’s job is to mimic the power draw of the stock incandescent bulbs to trick the computer to think that the bulbs are drawing the same rate of power so the vehicle does not throw any error messages.

Do I need error free bulbs?
If you own a European vehicle, you will most likely need error free bulbs. Many European vehicles such as Audi, Mercedes-Benz, BMW, Range Rover, Jaguar and many more use a CAN-bus (controller area network) systems that monitors the activity of lights on the vehicle to detect if they are operating or not.

Since LED bulbs draw far less power than the stock bulbs, the vehicle’s can-bus system detects the low power draw and determines that the LED bulb is faulty. To stop this from happening, error free LED bulbs have resistors that are built into the light which mimic the power draw of the stock bulb which stops the error message from occurring.

Error free LED bulbs are most commonly used for exterior lights such as the turn signals, head lights, parking lights, license plate lights and more. Interior lights typically do not need error free bulbs, but for certain vehicles, it is required.

To determine what type of lights you need, you can search the year, make, and model of your vehicle on our website. If you do not see your vehicle listed or if you have specific questions regarding what light to get, contact us and we’ll assist you with finding the correct light for your application.


There are so many error free LED bulbs to choose from, which one is right for my vehicle?
We carry various types of Error Free LED bulbs that come in different specifications and sizes; some of our products have a brief compatibility guide and lists the vehicles the bulb is compatible with and what light it replaces.

However, we also have products that are not compatible with all vehicles, if you do not see your vehicle listed, we recommend you to contact us with your questions and we’ll get back to you with a recommendation.

Back to Top

I have error free bulbs, but they still throw an error, why?
With vehicles that require error free LED bulbs, there is a specific way to install the lights to make sure that there is no error message. Please follow the steps below:
1. Take out the LED bulb and replace it with the stock bulb, turn on the vehicle, and confirm if the error message is cleared.
2. Turn off the vehicle and re-install the LED bulbs (make sure it is the correct side of polarity or else the vehicle will record the error message again). If the LED bulb is installed, but the polarity is incorrect, you will have to start the troubleshoot again from step one (1).
3. Close all the doors (trunk and hood if open as well), lock the vehicle, and wait 10-15 seconds. After this period, start up the car and turn on the lights to check for the error message.
This is a strange procedure to do, but what we have found in the past is that it does work out well for majority of the vehicles we’ve dealt with. If the troubleshoot above still does not work, please contact us and we’ll find an alternative solution to the problem.


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#3 Old 09-25-2017
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I've read different threads where people say they bought CanBUS LED bulbs but still had problems (fast flashing, warning light, etc.).
Are certain LED CanBUS bulbs better than others that won't give errors?
Or is there no gaurantee?
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#4 Old 09-25-2017
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Quote:
Originally Posted by jaconti View Post
I've read different threads where people say they bought CanBUS LED bulbs but still had problems (fast flashing, warning light, etc.).
Are certain LED CanBUS bulbs better than others that won't give errors?
Or is there no gaurantee?
Usually if you are buying on ebay from another 'country' then you are probably not getting true canbus error free bulbs
I have had great success with ijdmtoys

https://store.ijdmtoy.com/Shop-LED-B...-Car-s/262.htm

my car is even in one of the ads here:

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#5 Old 09-25-2017
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Remember all exterior led bulbs + interior trunk led require error free bulbs (they have resistors)
the rest of interior leds do not need error free
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#6 Old 09-25-2017
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and good info from savcom

https://www.slkworld.com/slk-r170-gen...us-system.html
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#7 Old 09-25-2017
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My God you're quick!

Thank you! Found them! I'm gonna give them a shot. Thanks again!
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#8 Old 09-25-2017
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No problem

which type you getting?

ijdmtoys are in california and guarantee/warranty bulbs for 30 days


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#9 Old 09-25-2017
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last bit of info

What are CAN-bus Error Free LED bulbs?
CAN-bus Error Free LED bulbs are LED bulbs that have resistors that are internally/externally attached. European vehicles are the typical candidates for these types of LED bulbs as the electrical system on these European cars have sensors that detect whether the light is working or not. Since LED bulbs draw far less power than the stock filament bulbs, the vehicle’s computer may think that the bulb is out so it'll throw an "error message" or "bulb out" warning the driver that the light is out; thus the name "error free". The resistor’s job is to mimic the power draw of the stock incandescent bulbs to trick the computer to think that the bulbs are drawing the same rate of power so the vehicle does not throw any error messages.

Do I need error free bulbs?
If you own a European vehicle, you will most likely need error free bulbs. Many European vehicles such as Audi, Mercedes-Benz, BMW, Range Rover, Jaguar and many more use a CAN-bus (controller area network) system that monitors the activity of lights on the vehicle to detect if they are operating or not.

Since LED bulbs draw far less power than the stock bulbs, the vehicle’s can-bus system detects the low power draw and determines that the LED bulb is faulty. To stop this from happening, error free LED bulbs have resistors that are built into the light which mimic the power draw of the stock bulb which stops the error message from occurring.

Error free LED bulbs are most commonly used for exterior lights such as the turn signals, head lights, parking lights, license plate lights and more. Interior lights typically do not need error free bulbs, but for certain vehicles, it is required.


I have error free bulbs, but they still throw an error, why?
With vehicles that require error free LED bulbs, there is a specific way to install the lights to make sure that there is no error message. Please follow the steps below:
1. Take out the LED bulb and replace it with the stock bulb, turn on the vehicle, and confirm if the error message is cleared.
2. Turn off the vehicle and re-install the LED bulbs (make sure it is the correct side of polarity or else the vehicle will record the error message again). If the LED bulb is installed, but the polarity is incorrect, you will have to start the troubleshoot again from step one (1).
3. Close all the doors (trunk and hood if open as well), lock the vehicle, and wait 10-15 seconds. After this period, start up the car and turn on the lights to check for the error message.
This is a strange procedure to do, but what we have found in the past is that it does work out well for majority of the vehicles we’ve dealt with.
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#10 Old 09-26-2017
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I doen't really have anything to do with can bus, it is just the load sensing circuits in the vehicle. You can use the cheapie LEDs you just need to apply a bit of OHMs law and calculate the missing amperage draw and fit the appropriate resistor to fool the sensing circuit.

the two formula’s you need is E /I x R and the wattage formula P / I x E
E=Voltage with the vehicle running
I=Current Draw
R=Resistance

P=Power in watts (The heat that is generated through the circuit running or the lamp and LED in this case)


p { margin-bottom: 0.25cm; direction: ltr; line-height: 120%; text-align: left; }
  1. A load resistor is used to draw more current, usually for the sake of tricking signal flashers or other "bulb out" indicators into functioning normally when LEDs or in some cases HIDs have taken the place of higher current draw incandescent bulbs.
  2. You will need to connect your New LED in series with an amp meter on your trusty multi meter and measure the current passing in the circuit, once you know the amperage (I) you can calculate the inferred wattage (P) by using Watts Law I multiplied by E = P
    Example #1:

    If you have a 35W HID system and your car thinks the bulb is out because it's not drawing the regular 55W that a halogen would, you need a resistor that will draw 20W.

    Watts = Volts X Amps, so 20W / 12V = 1.667amps, therefore 1.667amps need to go through that resistor @ 12V to make the 20W you need... so how do you figure out the resistance?

    ...You use the equation electronics revolves around, Ohm's Law.

    V = IR, I = Current (or Amps)


  3. so...

    12 divided by 1.66 = R

    R = 7.2

    You need a 7.2ohm resistor to pass your 20watts.. and you should use a resistor with as high of a wattage rating as you can.. using a 25watt will run very hot.. using a 50watt will run nice and cool.
    This is important Just think how long you could hold a 20Watt globe in your hand with it glowing at full brightness, it would eventually melt the wiring around it, by using a 50 Watt Resistor it is only working at half load and would be warm but not hot.



    Example #2:

    If your signal light bulb you replace with LEDs was 21W, and you're only running 9Watts of LEDs then you need a resistor to make up the other 12W.

    Watts = Volts X Amps ..so I = P divided by E so... 12W / 12V = 1A

    to Figure the resistance you need to pass 1A at 12V you use Ohm's Law ( now realistically you want to measure your car's output while running and use that number in these equations, probably 13.8-14.5)

    V = IR

    12 divided by 1 = R

    R = 12ohms

    Now only passing 12W, a 25W resistor would be fine.

    There we go! now everyone can figure out what load resistors they need.
If you have troubles send me a message I will try to explain it better.


Cheers Chaos...
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#11 Old 09-27-2017
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Quote:
Originally Posted by Captain Chaos View Post
... You need a 7.2ohm resistor to pass your 20watts.. and you should use a resistor with as high of a wattage rating as you can.. using a 25watt will run very hot.. using a 50watt will run nice and cool.
This is important Just think how long you could hold a 20Watt globe in your hand with it glowing at full brightness, it would eventually melt the wiring around it, by using a 50 Watt Resistor it is only working at half load and would be warm but not hot....
Good explanation but I'd be cautious about how hot a resistor can get. A 25W or 50W resistor dissipating 20W are both subject to the same heat energy. What differs is the size of the resistor and how effective it is at getting rid of its heat to the atmosphere.

You can get ceramic resistors or metal cased high power resistors and they will both dissipate the same load. The difference is that the ceramic resistor can get very hot by design (275°C) whereas a metal cased resistor will be designed to lose its heat to the atmosphere - or better still the chassis of the car - so will run cooler.

If you're adding resistors to the car look to buy ones like these and make sure the leads are fully insulated.

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#12 Old 10-04-2017
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My God...I think I have to go back to college. You guys are goooooood!

Ok, here's an update.
I've replaced my tail lights with Depo smoked LED tail lights and then used three Can Bus LED bulbs for back up, rear fog, and turn signal.
Everything is working perfectly with no hyper flash or warning message, and....I didn't have to use one resistor.

Parts used for back up and rear fog:
SuperBrightLEDs.com
1156-W26-CBT
https://www.superbrightleds.com/more...car/1326/3051/

Parts used for amber turn signals:
iJDMToys (purchased through Amazon)
20-044
Error Free BMW F30 F32 3 4 Series Turn Signal 7507 LED Light Bulbs

Also did my trunk light, glove box, and map lighting with LED. Everything looks great!!

Addressing the headlights and fog lights next.

Thanks again for the wealth of knowledge!
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#13 Old 10-04-2017
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I use this place http://www.ebay.co.uk/usr/car_tuning_shop_uk for LED'S
Not the cheapest but they work ok and have good service. Mine have been in for around two years. Click the links in my signature.
Headlamp bulbs that I would recommend are Philips X-tream and Osram Night breaker (used on my motorbike) for headlamps.
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Quote:
Originally Posted by Captain Chaos View Post
I doen't really have anything to do with can bus, it is just the load sensing circuits in the vehicle. You can use the cheapie LEDs you just need to apply a bit of OHMs law and calculate the missing amperage draw and fit the appropriate resistor to fool the sensing circuit.

the two formula’s you need is E /I x R and the wattage formula P / I x E
E=Voltage with the vehicle running
I=Current Draw
R=Resistance

P=Power in watts (The heat that is generated through the circuit running or the lamp and LED in this case)


p { margin-bottom: 0.25cm; direction: ltr; line-height: 120%; text-align: left; }
  1. A load resistor is used to draw more current, usually for the sake of tricking signal flashers or other "bulb out" indicators into functioning normally when LEDs or in some cases HIDs have taken the place of higher current draw incandescent bulbs.
  2. You will need to connect your New LED in series with an amp meter on your trusty multi meter and measure the current passing in the circuit, once you know the amperage (I) you can calculate the inferred wattage (P) by using Watts Law I multiplied by E = P
    Example #1:

    If you have a 35W HID system and your car thinks the bulb is out because it's not drawing the regular 55W that a halogen would, you need a resistor that will draw 20W.

    Watts = Volts X Amps, so 20W / 12V = 1.667amps, therefore 1.667amps need to go through that resistor @ 12V to make the 20W you need... so how do you figure out the resistance?

    ...You use the equation electronics revolves around, Ohm's Law.

    V = IR, I = Current (or Amps)


  3. so...

    12 divided by 1.66 = R

    R = 7.2

    You need a 7.2ohm resistor to pass your 20watts.. and you should use a resistor with as high of a wattage rating as you can.. using a 25watt will run very hot.. using a 50watt will run nice and cool.
    This is important Just think how long you could hold a 20Watt globe in your hand with it glowing at full brightness, it would eventually melt the wiring around it, by using a 50 Watt Resistor it is only working at half load and would be warm but not hot.



    Example #2:

    If your signal light bulb you replace with LEDs was 21W, and you're only running 9Watts of LEDs then you need a resistor to make up the other 12W.

    Watts = Volts X Amps ..so I = P divided by E so... 12W / 12V = 1A

    to Figure the resistance you need to pass 1A at 12V you use Ohm's Law ( now realistically you want to measure your car's output while running and use that number in these equations, probably 13.8-14.5)

    V = IR

    12 divided by 1 = R

    R = 12ohms

    Now only passing 12W, a 25W resistor would be fine.

    There we go! now everyone can figure out what load resistors they need.
If you have troubles send me a message I will try to explain it better.


Cheers Chaos...
I was just about to say that.....







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