Hiya,

I have a 2016 Ford KA MK2 and I'm trying to convert the rear lights to LED from Halogen, I have installed all the LED bulbs and have discovered that the ECU expects a certain circuit resistance on the lights so I've only been able to change the rear running lights and indicators to LEDs as they are on the same circuit as some halogen bulbs. 

I'm trying to figure out if there is a way to replace relays or reprogram the BCM or ECU to accept LEDs as if I have them all in at the moment they pulse (from the resistance check the BCM does) and then after 10 seconds or so they all go off assumably to protect against a short or something. 

I'm aware you can add a load resistor to the circuit to trick the car into thinking they're Halogen by increasing the circuit resistance but it sounds a bit janky and I wanted to know if there was a more permanent thing I could do by programming the car to accept them or by replacing some relays or something.

If anyone has any experience with this I'd really appreciate it, I was going to buy a forscan license and a FTDI based Canbus interface but obviously I don't want to do that without consulting people with experience first.

Thank you!

You can buy LEDs with resistors built in for exactly this purpose.

The BCM can't really be programmed to accept LEDs.  If LED's were an original factory option on the vehicle, you can switch between halogen and LED, but even then your aftermarket LED's would have to be of the same resistance as the originals.  And I'm not sure if any of the bulbs were optional LED's on the Ka.  (Some were on Fiesta/Focus)

Also not sure whether Forscan can access much on the Mk2 Ka as it's a Fiat 500 underneath.

2 hours ago, TomsFocus said:

Also not sure whether Forscan can access much on the Mk2 Ka as it's a Fiat 500 underneath.

As far as I'm aware FORScan won't work on the Ka, you would need to use Fiat programming.

 

1 hour ago, unofix said:

As far as I'm aware FORScan won't work on the Ka, you would need to use Fiat programming.

 

Ahh okay, ill have a look into whether it would be any help thank you.

3 hours ago, TomsFocus said:

You can buy LEDs with resistors built in for exactly this purpose.

The BCM can't really be programmed to accept LEDs.  If LED's were an original factory option on the vehicle, you can switch between halogen and LED, but even then your aftermarket LED's would have to be of the same resistance as the originals.  And I'm not sure if any of the bulbs were optional LED's on the Ka.  (Some were on Fiesta/Focus)

Also not sure whether Forscan can access much on the Mk2 Ka as it's a Fiat 500 underneath.

Okay I might try and buy the Phillips ones as the ones I bought don't have enough resistance, ill also have a look whether there is an optional led option for the ford Ka. Thank you 😊 it's a shame you can't just change the expected resistance on the ECU/BCM that would make this so much easier.

 

Thanks again both 😊

Try AutoBeam, they sell Canbus compliant LED's

https://autobeam.co.uk/

Many on this forum have used them.

 

On 12/28/2023 at 5:35 PM, unofix said:

Try AutoBeam, they sell Canbus compliant LED's

https://autobeam.co.uk/

Many on this forum have used them.

 

Only just saw this, I'll get a full set from here and report back. Thank you so much :)

Omg why are they so expensive? 💀 £121 to just do the rear tail lights (inc indicators and fog lights etc). Might save this upgrade for another time and just deal with only having half my bulbs LED