The CANBUS?

fryup

Need new dashboard bulbs...these ones on ebay seem to fit the bill...

but they come with a caution

Please ensure that the application area is not connected to CANBUS- please switch lights on without bulbs installed, you will need CANBUS compatible error free bulbs if an error shows up on the dashboard, standard LEDs will work if there are no error messages on the dashboard.

how critical is that?...and in laymans language whats the canbus ?

Toyotafanboi

It's not critical, it's just if you get non CANBUS compatable LED bulbs, they have a lower resistance than a filament bulb so the car will think it has a blown bulb even when it doesn't, so you'll have an error message on the dash constantly saying you have a bulb gone. That's the only issue. The more expensive LED bulbs have resistors built in to prevent the error message.

If your car is from the last 2 decades it probably has some kind of CANBUS system.

colm_mcm

What sort of car has a warning to tell you your dashboard lighting isn’t working?

Be aware that LEDs with distribute the light the same as a regular bulb so aren’t great as a dash upgrade

Toyotafanboi

Not very many, I've never come across any. Enlighten us, OP.

fryup

well its actually for the trip computer situated in the middle of the dashboard...the bulbs need replacing they've gone dim....there's no error message involved

mitsubishi colt 05

corks finest

Toyotafanboi wrote:

Not very many, I've never come across any. Enlighten us, OP.

Skoda fabia does AFAIK/remember

colm_mcm

fryup wrote: »

well its actually for the trip computer situated in the middle of the dashboard...the bulbs need replacing they've gone dim....there's no error message involved

mitsubishi colt 05

If it didn’t come with LEDs from day 1, I’d just use the original bulbs. If it’s designed to take bulbs and you fit LEDs youll probably get spotting and uneven distribution of light.


Also, this might be the answer
https://youtu.be/00X7mpr0EVw

fryup

^^^^^^^

no i tried that, makes no difference

Huawei Gallagher

With modern cars, there are loads of electrical gadgets and sensors reading data from everywhere eg exhaust temp, airbag and so on. If you were to run a wire to each sensor in the car the wiring loom would be 12 inches thick!

Now picture an office with computers and printers and wi fi devices all connected up with one cable. You can log in to one of the computers on the network and send a message to all the devices and also check if each one is working correctly. A CAN Bus network in a car works in a similar way. To simplify it a lot, the Brain of the car sends a message along the one cable asking "ARE YOU GUYS WORKING OK?" to perhaps 20 devices connected to the cable. The lambda sensor says "I AM FINE", Airbag says "I AM FINE", Air Fuel sensor realizes he isn't feeling well and says says "I AM SICK". i assume that this is how the readable fault codes are generated. The sensor devices etc. also report their readings using the network.

So I assume what they are saying about your bulbs is to switch on the lights without bulbs to see if an error code pops up on the dash, if it does then it means your bulbs are themselves devices connected to your cars computer network, and so you cannot use standard bulbs without fancy electronics in them. If no error code comes up standard bulbs would be ok and the bulbs are not part of the computer network.

I would err on the side of caution and go straight to your cars main dealer for the exact bulbs for that car, they cant be that dear.

I am not a Mechanic so above may be oversimplified but will give you an idea of what CAN bus is, its more of less a computer network thats in your car. Its in the same family as LAN which is in your house most likely.

fryup

^^^^^^^^^^^^^

excellent post, very concise.....are you a lecturer by any chance?

MrCostington

Toyotafanboi wrote: »

It's not critical, it's just if you get non CANBUS compatable LED bulbs, they have a lower resistance than a filament bulb so

Sorry to be the pedant, but surely a higher resistance (as draws less current) hence the CANBUS thinks the bulb is open circuit?

Huawei Gallagher

fryup wrote: »

^^^^^^^^^^^^^

excellent post, very concise.....are you a lecturer by any chance?

I only lecture people on the Internet with my half baked views :pac:

I have an I.T. Degree, so I learned about the different types of network.