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For my 2013 W204, I purchased Spyder branded tailights and while they work just fine as lights, I get ECU errors constantly that say "check tail lamps".
For their part, Spyder will not accept a return on these because I bought them from an Amazon seller and their customer support people actually said buying from a discounter with an amazon store "changed the warranty" I'm eligible for.
What they did say was that it sounded like they had a bad batch of resistors and that was all that was wrong. Can someone recommend what type of load resistor I can splice in or crimp in to eliminate the constant errors I get?
Spyder has been horrible to deal with. They just said if I'm out of warranty, "buy new ones". they wouldn't go into any details. I did find this link on those tail lights that refers to RT256 resistors, if that means anything.
No, they won't even discuss a part replacement. They have been extremely "punitive" about it. They wouldn't tell me "if" there's a replacement part, let alone the specs of a replacement part. A support person named "Me and *&^%$# down by the schoolyard" said, "All you can do is buy a new pair", even though these are less than a year old. They refuse to grant me a warranty because I bought them from an amazon seller and basically made it sound like I bought them from a guy in a trenchcoat on the street when I did that.
I am hoping that like others who have flickering problems and things like that, I can add a load resistor without too much trouble and get rid of the ECU errors. The link I provided before shows several pics and one of them has some specs.
My guess is "resistor RT256" means it's a 25 watt resistor with a 6 ohm current load. But this could be a completely arbitrary bull**** naming convention. If my guess is right it means the resistors are underrated for the operating voltage of the W204 which is about 13.6v with the engine running.
A 6 ohm resistor subjected to 13.6v would be pulling 30W of power (using the equation Watts = (Volts^2)/Ohms). So if that RT256 resistor has a max rating of 25W it will overheat and eventually die, which sounds like what happened to you.
For comparison, the Morimoto resistors are rated to handle up to 50W of power. What you are ultimately trying to do is simulate 42W of power draw; the taillights originally are two 1156 bulbs with draw 21W each. You would need a 4.4 ohm resistor to exactly simulate this (42W = (13.6V^2)/4.4ohm) but you'll be fine using a 6 ohm resistor since the electrical system needs to see 20W or so to think everything is ok.
So in short, yes the resistors you can get from AZN Optics will work. Otherwise you can try www.digikey.com for industry suppliers.
That's great news, Shimee. Thank you. I've seen some videos about installing resistors and some of them have a pretty simple "crimp" plug where there's no splicing and capping. I really don't want to get involved in pulling the "plugs" apart and am hoping its plug n play.
Eh it's not gonna be plug n play unless you buy exact replacements for the RT256 resistors. Looks like they have a short lead (red and black) coming from them which terminates at a plug that connects to a lead coming from the tail light itself. You're gonna have to cut the lead from the RT256 resistors and solder them to the new resistors you buy. That or use butt crimp terminals.
You are also going to have to mount the new resistors to metal because - the Morimoto resistors or golden resistors - will get quite hot under load and can melt plastic and wires.
I would suggest using Posi-Taps instead of T-taps. They create a better connection and leave a small pinhole behind, whereas T-taps shear away the wire jacket on two sides eventually causing the wire to break.
Looking to how-to instructions to add load resistors - 2011
Resurrecting the thread!
On the rear taillight carrier for a 2011, it's one plug cluster that clips to the carrier. I have added all LED, and would be nice to get rid of the error message. No clue how to easily determine which wire in the plug cluster goes to which bulb, or which bulbs trip the error message. Assuming all use the same brown ground. All the videos I've seen only deal with the earlier models that had 2 wires going to each bulb.
On the same note, interesting that when I add the 192 LED parking bulb to the top row, the 1156 LED next to it goes out. If I replace the 192 with the old incandescent, the 1156 LED works. It's the only arrangement that causes a light failure.
It's been a while since I changed backup light to very bright white LED which will cause error message without resistors. I used 25W 10 ohm power resistors, epoxy glued to adjacent metal to spread heat out. Car is not running so voltage is not the highest. I put it in reverse for about one minute, and 25W resistor only got warm, I can leave my finger on. With engine running it would be warmer but will not be hot. Car running in reverse will not be very long so I am sure 25W in my case is okay.
I soldered resistor wires on the light module therefore more reliable than non-solder connections.
Resistor location is not so much of any issue as how to find and isolate (if needed) each offending bulb. Assuming that all the 1156 are triggering the message, so that means about 5 resistors to install, right?
Not all my rear lights are LED (see picture), my front are all LEDs. In my case, the only bulb that causes error message is the backup lights. I don't remember and don't bother to find out which bulb is which in the rear.
Why not all LEDs in the rear? I either could not fine a good bulb at the time, or was not highly interested as time went on.
In my case, changing all the rear bulbs to LED was fine except for the top row with the parking light (192) and the 1156. Either one or the other, otherwise one of them won't light.
This is my configuration that works, aside from the error messages. Just wish I could figure how why I can't have two LED's on the top row. 5W parking light incandescent is 13v, and the LED version is only 12.
I tried swapping P21W LED into three incandescent bulbs in my above picture, all three cause error. Now I believe I stopped changing all to LEDs because too much work.
My question is are there LED bulbs CanBus ready? Many claim theirs are CanBus ready but is it really? And the relay that controls turn signal is CanBus ready, for W204?
I bought one relay for my 2002 Infiniti QX4 and it works with LED bulbs, no fast flashing, but the clicking sound is too low when I talk I can't hear the sound.
I tried swapping P21W LED into three incandescent bulbs in my above picture, all three cause error. Now I believe I stopped changing all to LEDs because too much work.
My question is are there LED bulbs CanBus ready? Many claim theirs are CanBus ready but is it really? And the relay that controls turn signal is CanBus ready, for W204?
I bought one relay for my 2002 Infiniti QX4 and it works with LED bulbs, no fast flashing, but the clicking sound is too low when I talk I can't hear the sound.
All the bulbs I've seen that fit our car are from China, and not manufactured to any kind of Mercedes standard. They fit and they (mostly) work. That's it.
At this point, since all the LED lights work great, I really don't mind the left/right tail light error messages. 2 clicks and they are gone, but I don't always even care. The resistors sound like too much work for too little effect, plus the fact that no one seems to have a good solution to fit resistors to our style carriers. LEDs don't harm the electrical system in any way, and besides being far cooler, they use less voltage.
Tried on rear left side, now all LEDs. No error. I de-soldered wires and popped load resistor off. Will order another set for rear right side.
I bench tested this LED. At 12V it draws 0.88A, about 10W. Online info tells me for Halogen P21W bulb it is 25W. Previous backup LED draws only about 0.2A which causes error message.
That's great. I actually just picked up some different 194 and one set of 1156 that are CANBUS ready. Fixed my top row problem. Hate to spend more money to change the rest (again) so I may just live with the nag message for a while
Finally I got both rear side all LEDs. Bottom two LED lights are brighter than factory halogens, of about half wattages. Now I know an error free LED will have heat sink to dissipate extra heat caused by built-in resistor, or current controlled chip.
My previous turn signal LED does not have any heat sink around. I don't know why I missed that when I ordered it.
I'd like to try changing the front amber turning indicator bulb to LED. Given that it's a wedge bulb, is there one out there that might work and not cause error?
I'd like to try changing the front amber turning indicator bulb to LED. Given that it's a wedge bulb, is there one out there that might work and not cause error?
I will take a look what I have after I get off work today.
I lost info where I bought the front turn signal LEDs. Attached are pictures. It is two element LED, to increase brightness I parallel two elements by soldering two pins together on both side. It has polarity. They are not bright enough to my taste but I can see them flashing at distance will not miss the signal.
I am sure if you buy an error free or CANBUS ready LED, it will not give error messages. There should be many available.
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