LED Bulbs & CANbus Error Codes – How To Fix (with video)

LED Bulbs, CANBus Error Codes & How To Fix Them

In this post, we’re bringing you an episode of ABD TV where we aim to answer all of those burning questions, clear up the confusions and leave you brimming with knowledge.

Today we are tackling the murky waters of LED bulbs, more specifically the hassles of the dreaded CANbus error codes.

So what do I mean with CANbus Error Codes?

Well more modern vehicles are all about sensors, warnings and messages. When something goes wrong on your car, you’ll often get some sort of notification of this on your dash. This could be a simple warning light illuminating, or an actual written message.

Canbus Error Message

Your car is full of these sensors and they will monitor many many systems throughout your vehicle from fuel injection to brake pads to seat belts.

In the case of bulbs, your car will let you know when one of the exterior applications has failed. This checking/reporting is commonly referred to as a CANbus system.

Of course these error messages are very useful and a great addition to modern vehicles, so what’s the problem?

Aftermarket LED Bulbs causing Error Codes

LED Car Bulbs

The problem is with false positives created with aftermarket products such as LED bulbs.

The most common way a canbus system will check if a bulb is working or not is to measure the resistance on the circuit. Some vehicles measure the total circuit resistance, others check individual bulbs. But they are checking for the characteristics of a normal filament bulb.

One of the core selling points of an LED bulb is the lower power draw. Who doesn’t want an extra bit of fuel saving! Especially with the likes of caravans and motor-homes.

I won’t bore you with the physics here, but less power means there is more resistance (P=V²/R). Your vehicle CANbus system is therefore going to see something it’s not expecting and flag up the error message. In some cases it will even cut power to that circuit, meaning your perfectly good LED bulb fails to illuminate.


Fixing the Error Codes

There are 2 main ways to overcome this problem and I’m going to run through both of these below:

CANbus Compatible LED Bulbs

The first and most simple solution is to fit a CANbus compatible bulb.

Canbus LED Bulbs

Bulbs like the Twenty20 Cree LEDs and some of the Ring Premium range have additional resistors built into them to adjust the characteristics of the bulb. This brings them closer to the parameters that your car is looking for.

As these are a direct replacement for your existing bulbs, these would always be our first recommendation of what to try.

In 95% of cases, this will be enough to overcome the issue. However some vehicles can be particularly fussy and they still throw up an error.

The issue is with the amount of resistance that would be needed for it to match a filament bulb. It would simply be too big and be too hot. The heat from a resistor would cause it to fail almost instantly.

Therefore the manufacturers can only try and get as close as they can and hope it falls within the required levels.

In cases where you simply have a super fussy vehicle, and even CANbus LED bulbs don’t cut it, we have to move onto our second option and add the resistance another way.


Resistor Kits for LED Bulbs

This is where resistor kits like this one from Osram come in.

This might sound like it’s getting complex but it’s actually very straight forward. You can see how this is done in the video at the top of the page. But the general concept is as follows:

Canbus Resistor Kit

A typical bulb holder that you would have in your car will have 2 wires going to it to supply the power. One for the positive and one for the negative. It’s not important in this case to know which is which, just that you have the correct 2 wires for your LED bulb.

On our resistor, conveniently enough, we also have 2 wires.

Simply use the supplied scotch locks to splice together one leg of the resistor to one bulb holder wire, and the other leg to the other. This is called connecting in parallel.

Once done, this adjusts the resistance to the correct amount without it impacting on the bulb itself.

And that’s it, simple.

Resistor Kit Installed

Now you are an expert on LED bulbs and canbus issues. Remember, if you have a modern car with a CANbus system, first try a CANbus compatible bulb. If that doesn’t work, break out the resistors and you’ll be up and running in no time.

If you have any questions on this, feel free to ask them in the comments below.

Also if you have any other general product questions you’d like to see us cover in a future ABD TV episode, please send them in either via our social media accounts or via email.

Related Information

  1. Overview
  2. Aftermarket LED Legalities
  3. LED CANBus Errors
  4. LED Headlights
  5. OEM LED Units


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Paul Platt
1 year ago

Hi there I’ve just bought some LeD bulbs from you I have put the indicator ones in and they flash fine but on the dash the indicator signal flashes fast and the sound is fast but the indicators themselves normal speed what do I need to do to sort this thanks

paul norris
1 year ago

hi, my son has a 2014 vw polo, he has fitted dynamic indicators which work with ignition on but when the engine is running he gets 3 flahes then they cut out. would the resistors shown work to cure this problem?

Ian Mather
1 year ago

I tried installing H11 Twenty20 Cree LED 12V Canbus Foglight Bulbs to my For Transit Connect but I have CANBUS issues. Bulb flashes 4 times then stays off. I installed a 55w resistor across each bulb connection and same error. Bulb flashes 4 times then stays off.

Ports Garage UK
1 year ago
Reply to  Ian Mather

If you have resistors on both bulbs it’d probably indicate your vehicle’s CANBus system is just hyper-sensitive.

Those bulbs have resistors already built in so if additional resistors aren’t working – it’s usually down to the vehicle.

You’d be better off plugging in an OBD-II device and just turn off the part of the system that checks the headlights.

Leslie Turner
1 year ago

Hi, I’m confused with what size canbus resistor’s should be fitted to. DRL 21w/5w led , thanks, Les

Dean Michael
1 year ago
Reply to  Leslie Turner

Hi Leslie,

If you know which filament is presenting the CANBus error then you would get the resistor that matches the wattage.

For example, if it’s the 5W part of the bulb giving an error then the 5W resistor will suffice.

A safer method would be to buy the 21W as this should cover both filaments.

Francis jones
1 year ago
Reply to  Dean Michael

With a combination bulb (stop and tail in one socket do you need a separate resistor on both aspects of the bulb?

Jay Robinson
6 months ago

hey what’s up? thanks for the above info; very useful. I’ve installed the H7 led bulbs about a year ago and now the passenger side low beam flickers. What do I do to correct it?

Tom Easby
1 year ago

Hi There. I have installed 2 new LED bulbs, brake light and indicator lights, on either side of my car. However, they are both connected with one wire. They are both 21w bulbs but connected to the same wire. This is on my 2015 Vauxhall Corsa. Would I still be able to install a 21w resistor to this one wire for both bulbs or would i need to double it so maybe go for one nearest to 42w? let me know!

Noel Bush
2 years ago

The ideal,is to be able to swap out the old style flasher unit and replace it with an electronic unit. Unfortunately car manufacturers are fitted with blinders and just refuse to do it, even in the 2020, just to save a few cents,although with modern parts manufacturing I would doubt that there is any cost difference.

Not to be unfair, there are a few sensible Car makers who do fit electronic units plus LED bulbs, cynically though, they make their Led bulbs as an integral unit ,hence no easy bulb swap, large cost for replacement. Definitely not customer friendly, its all about the bottom line.

7 days ago

Good morning, I have a 2006 Volvo S60 I bought it a year and a half ago and had to replace the driver’s side low beam bulb4 times already. I am careful not to touch the bulb as I know that oils from your skin will cause them to over heat. Is there a solution to the problem? Is this a Canbus wiring issue?

3 months ago

Good afternoon, Can you tell me if the 2014 Smart fourtwo would accept aftermarket sidelight LED’s without causing Canbus issues. Many thanks.

Kacy Buckner
3 months ago

So I bought some LED headlight bulbs for my 2008 scion xb and when I replaced them I now have 2 dash lights on. The traction control and my check engine light is on. Anyone know why?

Derrek Thomas
7 months ago

So i have a 2018 silverado ltz and i have the tri-projection led’s an they came with resistors already wired in the headlights are fine the drl/turn signal hyoer flashes after 3 normal flashes an gives turn signal lamp out warning, none of the lights are bulbs they are boards can i install canbus decoder to cancel warning msg?

Michael Danaher
7 months ago

Hi I have replaced the interior lights in my wife’s golf with LED bulbs, but they do no go out after 10 seconds or so like the old bulbs did. They do go out when you lock the car, but not while you get in and drive off. Any tips> Michael

Dean Michael
7 months ago

Bulbs don’t ask for power, the vehicle gives it to them.

Depending on the situation, there might be just enough charge going to the bulbs to light them up.

A simple fix would be to try a different range of bulbs or fit a resistor kit to the wiring behind the bulb.

7 months ago

Hello i have a volvo s40 mr2 2004. I install samsung mover f3s h7 and the low beam failure still appear. I read at some forums that many have this problem. what i should do? The lights works fine but i have that error on my panel. I think the square box that they have is already canseler or not? Any help please? Maybe to do everything led it will solve the problem or not?

8 months ago

What will be the best salaution to not to let load resistor to get so hot anything I can do to secure it from burning anything

John Osgerby
9 months ago

I have just fitted Ring Premium LED bulbs (RW501CBLED 12v W5W 501 LED) to sidelights of Ford Ka 1.2 2001 as wanted to increase visibility of daylight running lights (sidelights). They were fitted to replace other LED side lamps that worked but brought up dashboard warning (lamps out). The Ring are bulbs advertised as suitable for my car and CANBUS. The bulbs do not work at all and warning light remains. I have replaced the old filament bulbs. Any ideas before I send them back?

Dean Michael
9 months ago
Reply to  John Osgerby

Hi John,

Unfortunately nothing is ever guaranteed with aftermarket LED’s and CANBus systems.

Whilst a bulb is CANBus compatible, it won’t be fool proof and may still cause errors.

This isn’t specific to all Ford KA’s though, we’ve found it’s specific to the vehicle.

The best options would be to either try a different range of bulbs or to fit a resistor.

10 months ago

Hi I’ve bought canbus error free h7 leds for my 2011 Ford Focus put them in the car and they work fine when the engine is off but as soon as I start the car they go off can you help?

Dean Michael
10 months ago
Reply to  Scott

Hi Scott,

Unfortunately no aftermarket LED’s are guaranteed to be error free.

Your best options would be:

  1. Try a different range of LED bulbs
  2. Speak to an auto electrician (they may use an OBD-2 to fix)
  3. Fit a resister to the cables

Keep in mind, some vehicles are more/less sensitive to the resistors built into the bulb due to a number of factors.

Kind regards,

stuart aston
1 year ago

i’ve changed the headlight for xenon one on a vito, i cannot get them programmed to work at mercedes so thinking of doing via a relay per element this brings on a bulb failure as the power for the relay is approx 1.5w, is it just as simple as fitting a approx 5o watt resistor?

Michael J Hall
1 year ago

Hi I have a Mercedes Vito. My small car trailer lights are not a problem, but with a caravan which has a total of eight extra bulbs. 2 front marker lights 2 side marker lights 2 number plate lights and two rear side lights. When the lights are turned on they go off and on several times then go offpermanently . Can you advise. Regards Michael.

Henry Maguire
1 year ago

You supplied me with campus bulbs for my 12 Skoda yeti 1.6 diesel my warning light is still showing check left brake light plus registration plate light even though they are still working is there a special way of putting them in and is common to happen on this particular model car

Dean Michael
1 year ago
Reply to  Henry Maguire

Hi Henry,

Unfortunately, it’s vehicle specific and results can differ between vehicles from the same line.

The best way to remove warning errors is to fit an LED resistor kit.

Richard Revill
1 year ago

581 Twenty20 Impact Cree LED Canbus Amber Bulb 12V PY21W Order ~867827

I have fitted these to the rear indicators to my Ford Kuga 2015 and if I switch on either right or left indicator the indicators flash much quicker as if a bulb was not working, I do not have any error warnings, if I put the hazards ie all 4 indicators they flash normally what is wrong please.

Thanks Richard

Dean Michael
1 year ago
Reply to  Richard Revill

Hi Richard, If you experience hyper-flashing then it’s worth swapping what you’ve purchased for some LED’s designed to prevent hyper-flashing.

I would recommend the 581 HF0 LED’s by Twenty20.

They are designed to prevent against quickly flashing LED’s and are incredibly bright compared to a standard bulb.

Peter Richardson
1 year ago

Hi, is there anything on the market at 70w for 24v truck H7 headlight bulb

1 year ago

My Drl’s power on while the car is off for a few seconds periodically… I have a 2020 Camry and I purchased a set of aftermarket drl/fog lights for amazon

Ron Longhurst
1 year ago

Would I need a resistor for each bulb or can I get 1 for the whole system?

Philip Reeve
1 year ago

I have replaced the 36mm filament number plate festoon lamps in my Saab 95 Aero (new generation) of 2011 for Osram LED C5W cool white lamps (SV8. 36mm)

The lamps are good but the Saab throws up an error on the dash of lamp failure.

I have then purchased the Osramr 5w LEDriving CANBUS Control unit.

I have wired these in the system and the error message is still there.

However, if I add only a 5w filament lamp into the circuit (no other devices attached) the message disappears and obviously reports that all is ok.

Why am I getting this, when the Osram 2x 5w canbus resistors are placed in the circuit the error is still presented on the dash. What is going on!

Regards Philip

2 years ago

Hi, My sequential leds work fine with ignition on then start engine running lights stay on sequentials stop

Joseph Bonello
2 years ago

Thanks for the information above. As you state in your video one of the reasons for using LED bulbs is to save power. However in cases where you have to connect a parallel resistor to keep the CANbus system happy there will be no power savings. The LED bulb and resistor in parallel will draw more or less the same current as a standard filament bulb. This must be the case if the CANbus system is to ‘see’ the expected resistance as a normal bulb since R=V/I. The voltage V is standard battery voltage.

Dean Michael
2 years ago
Reply to  Joseph Bonello

Hi Joseph, You are correct.

If a driver only wanted the LED bulbs to reduce the power consumption then a resistor would be pointless.

The majority of drivers choose LED’s for the light output, longevity and reliability and fitting a resistor will not affect any of those. Most drivers will not consider power consumption unless there is something wrong with their vehicle such as a faulty alternator or battery.

Most modern vehicles can cope with large amounts of power usage and older vehicles very rarely have any sort of CANBus system so a resistor wouldn’t be needed.

2 years ago

So I take it you have to use a resistor kit for every bulb you’ve changed to led.

Dean Michael
2 years ago
Reply to  Gerrard

Hi Gerrard,

No. You would usually only fit a resistor kit to bulbs that display a CANBus error.

You wouldn’t need a resistor for every LED bulb.

2 years ago

Good afternoon, I have 2 Osram H7 LED bulb and I have an error on dashboard. Can you tell me please what Canbus is beter to use between Osram LEDCBCTRL 103 and Philips H7 Canbus. I know at Osram canbus I will have to change the conector. Thank you!

Dylan Mateer
2 years ago

can you still use the led light bulbs and just ignore the censor saying the light it still out?

Dean Michael
2 years ago
Reply to  Dylan Mateer

Hi Dylan,

A warning light should not have any detrimental affect on your vehicle’s performance.

David Sheldrake
2 years ago

I fitted your CANbus LED stop/tail light bulbs to my 1993 Yamaha GTS 1000 and although it didn’t have a CANbus system as we know it today it did have an early ABS system. The bulbs really upset the ABS system which created error codes. It was only after fitting Osram resistors that the problem was resolved. I have to say that the bulbs give a great light and hope they stop me getting squished from behind.

Lucas Bayle
2 years ago

Great article! Looking to use 10W DRL leds. Am I able to use 21W osram resistors? Short of the long is, do you have to use the same watt resistor as the led’s or can you use higher resistors?

Thanks in advance

2 years ago

Hello, I have yellow (ish) halogen DRL bulbs on my vauxhall insignia and want to change them for led bulbs and have no error messages / bulb out on the dash. Which rating of osram resistor kit would be suitable? Thanks.

2 years ago

Hi I have a Boxster 987 2005, in the rear lights I have the following bulbs

tail/ stop, tail/fog , tail light only plus indicator and reverse, I purchased 20 twenty led’s from yourself but all throwing up errors, could you tell me which resistors I need to order from your site for the following bulbs I ordered

the bulbs I purchased were

1 x 380 stop/tail, 581 rear indicator, 566 rear fog, 382 reversing – need to order another pair of 380’s as thought there were only 2 tail

Graham smith
2 years ago

Hi, I’ve used yourselfs and recommend you to a friend who has purchased some H7 and H15 20twenty led bulbs for his 2018 ford transit, the H7’s work perfect no faults or canbus errors but the H15’s have strange things happening, as they are drl’s and main beam in one when we start the van the drl’s come on but after 30 seconds go off but if you use the indecators ie indecate left the left drl comes on and stays on, and same for right, if you turn the head lamps on then off the drl’s stay off? Im thinking when you use the indecators it gives more resistance in the earth side as this is common earth in the lamp for all bulbs and so the canbus see’s this and turns the drl for that side on, my question is do i fit some led resistors to the lamps to over come this along witb the 20twenty H15 bulbs? Would this work and which suze resistor would i use? Thanks for any help.

Thomas L Hunsinger
2 years ago

I put new led headlight in a 05 ultima se r the high beam bulbs work but the regular beam come on for 1 second then shut off I put cancelors on But same problem with wires tested both ways for polarity

2 years ago

Adding a resistor defeats the main advantage of leds, namely much less power usage.

Noel Bush
2 years ago
Reply to  George

True, but the main reason everybody changes to LEd is because of their greater light output, plus they have a much increased life span, the small amount of power lost through the resister is not a deal breaker.

2 years ago

Hi I have fitted new led trailer lights my boxer van is canbus system I don’t think they are compatible as the indicators flash through the tail lights . when engine is running the indicators are flashing as they should I have another trailer which is working fine with led lights not imported ones

Joseph Carter-Swales
2 years ago

Hi there, I have recently purchased some LED front indicators for my car, but upon installation I noticed they were hyper flashing, so I am looking for a resistor but I am not sure which one to get, I found a Canbus one on Ebay but that said it was for headlights only. Any help would be greatly appreciated.

2 years ago


Adding a resistor naturally looses your gain in reduced current … energy goes to heat … :(

Newer cars must account for this problem ..


Can parameters in the CANBus part of the computor be adjusted so the problem is solved?

2 years ago

Hi we changed all our bulbs in the Motorhomes toLED and our light is on, my question is do you have to fit 1 of these kits to all the bulbs to reset the dash light.

Ray McGuinn
2 years ago

Hi I have a replacement Passenger Headlight for a Audi Q5 67 plate but the indicator is solid orange and never turns off any hints or tips please, I have had the ballasts coded but the orange indicator is always stuck on a solid orange colour Thanks in advance.

Rob Reeves
3 years ago

Hello, thanks for that I now understand what can bus error free means. I fitted some T5 leds after fitting other led else where they failed, flickering. I have replaced them but all the old switches on my dash with the non led tiny bulbs in, have failed. The bulb itself looks in good order although it is hard to see because it’s so small. All these bulbs should light when the cars lights are switched on, but only the leds are illuminating. It is an old Japanese 4×4 and all the bulbs have worked together until the T5 started to flicker. Cheers Rob.

3 years ago

I used 21w and 5w osram resistors for w21/5w led day lights. 21w working without problem but 5w still gives error even with resistor (connection seems fine and resistor gets hot). Do you have any idea how to fix it?