KnIgHtCoM

I used the ones you suggested: 25W/30-Ohms. Can you explain how the different values affect the heat dissipation? I didn't quite understand your previous post.

my530i

Power(heat) = (Voltage)^2 / Resistance
Voltage is constant = 12V
Therefore, the higher the Resistance, the lower the heat, and vice versa.

Resistor acts as Current limiter, so according to Ohm's law/equation:
Voltage Drop = Current x Resistance
=> Current = Voltage Drop / Resistance
Voltage Drop is constant = 12V
The higher the Resistance, the lower the current. If current is too low, LCM complains. That's why when you connect rear LED lic. plate light, it draws only 0.1A or so which is way below LCM allow. So, this causes LCM complains.
You then add a resistor to drain some more current to make LCM happy, but if you drains too much (too small resistor value), LCM stops providing current and it turns off the circuit.
If you drain too little (too big resistor value), LCM complains that too little has been drawn.

Therefore, there is one optimal resistance value to use in combination with LED light, and we need to find out by trial and error starting from the point that LCM complains and keep adding resistance until error is gone.

KnIgHtCoM

After several 1hr+ night drives, I have not had any issues with the resistors getting too hot and melting the wires.

But as I was driving back home today, I got an lamp out error on the right plate lamp. It appears the power on the right side is dead. I tried swapping the bulbs and even putting my halogen lights back in, but still no power. The left side works fine.

Since only one side wasn't working, I didn't think it was a burnt out fuse, but I checked anyways in the trunk and in the glove box and didn't find any. Are the fuses for the plate lights under the hood? I couldn't figure out how to remove the covers.

Lastly, I removed the trunk liner to inspect the wires but didn't notice anything that looked unusual.

I need to take my car to the dealership to get serviced anyway, so I'm putting the stock halogen housings back in for now so they can look at it. Hopefully they don't have to rip apart the car to get it to work.

Any help from you guys would be appreciated!

my530i

The current that LCM expects each license plate to withdraw 0.3A, and you're using both 50-ohm resistor and LED light. It'll withdraw somewhere around 0.24A (resistor) + 0.02A (LED) = 0.26A. I don't see any problem at all. Turn car off and turn it back on to see if light is on again.

I'll check it out once I have the light from Garry.

KnIgHtCoM

I'm using a 25W/30-Ohm resistor, but I get the same results when i plug in the halogen bulb too (even after a few restarts). So it's not the resistor.

my530i

When you plug in the halogen bulb, you have to disconnect the resistor.

KnIgHtCoM

Yeah, I removed the resistor.

my530i

Recycle the ignition. Any warning on i-Drive?

KnIgHtCoM

Fred, you the man! I recycled the ignition and that did the trick (I forgot to try that). The resistors must not be withdrawing the optimum amount of amps giving the fault in I-Drive and shutting off power completely.

lcc014

Hi,

From this invoice, which part number is the new connector and which one is the pin ?

Thanks,