Strange electrical issue
 

Proud new owner of a 2013 Toyota 86, the car runs great however it has a strange issue that seems to affect all the lights of the car (except the dash). The car has Valenti taillights and the whenever I brake 3 LEDs on the whole strip often don't light up, the same goes for the other taillight but different LEDs don't light up (however it doesn't happen as often as on the other side). The interior light sometimes flickers whenever the engine is on and a door is opened. Recently I have also noticed one LED on the right DRL also doesn't turn on. I would have gone and guessed the LEDs are burnt on the taillights and headlights however since the interior light flickers too it makes me wonder if there is something more to the issue. Any suggestions?

Welcome to the gang - :clap:

I'd suggest you fix the lights that don't work first, then the interior light may right itself.

Valenti's seem to be well known for having led failures.

My cheap ebay led interior lights flicker as well, that's directly related to them being cheap ebay lights

That's definitely something I had no idea about, I thought Valenti's were quality made, guess I was wrong.

About the headlights, are the DRL leds known to burn too? I have one led on the right headlight drl that won't turn on. Suggest new OEM headlights or aftermarket?

What condition are your battery terminals in? Next question: Do you have a multi-meter to use in order to troubleshoot electrical problems?

Battery terminals look fine to me, will post a picture tomorrow.

I do not have a multi-meter but i should definitely get one soon.

Here's a picture of the battery

https://ibb.co/nQ8sh0f

I have noticed the battery seems a bit old but it IS the upgraded 65 Ah one. Definitely need a multi meter to figure out if it's on its way out.

Your negative terminal doesn't look bad, but you should lift that plastic terminal cover off to look at the positive terminal also.

A multi-meter is a good tool to have for troubleshooting electrical issues, and any good technician needs to own one, (most of us have more than one) but you really need to load test your battery and charging system if you suspect either of those to be an issue and a multi-meter isn't really the right tool for that.

However, the problems that you were describing in your original post seem like they may be due to the installation of your aftermarket lighting. If the installation was done poorly using connectors like T-taps that pierce the wiring insulation, those can eventually cause problems like you are describing with the interior lights. Especially if a previous owner tapped into the wrong circuit.

I think you are correct in suspecting that the Valenti LEDs are going bad, but that wouldn't cause the problem with the flickering interior lights. You should closely inspect all of the aftermarket wiring that has been installed into your car. You can always unplug the taillights from the car and continue to troubleshoot to see if the flickering goes away, but I will bet that there's something else causing that issue.

I changed the interior LED that was installed by the previous owner and now the problem is gone, so got that taken care of.

I have however noticed the left HID flickers usually whenever i don't give enough gas and the car is about to stall, so that makes me wonder if the battery is at fault and going bad.

The headlights are stock, they're the original ones that came on the car from the factory and they have HIDs and led DRLs on them, these ones to be precise:

https://www.jdmyamato.com/jdm-toyota...nuine-oem.html

So other than the Valenti taillights there's nothing aftermarket on the car

Glad to see that you figured out the interior light issue. Have you had to jump start your car at all since these issues started occuring?

I've only had the car for about two weeks and i fortunately have not had to jump start it. The cold start does sound a bit strained though

If I were you, first thing I would do is purchase a decent multimeter. Then I would definitely get a load test done on the battery and charging system after removing both battery terminals to do a thorough cleaning and inspection and spray both with terminal protectant afterwards. Inspect your cables where they are crimped at the battery and where they lead to the fuse block and where the negative cables connect to the chassis and engine ground points. Start with the basics.

Any lights will flicker if the RPMs are dropping to the point where the car is about to stall. You need to address that issue before trying to trouble shoot flickering lights.
A check of the battery is a good idea but it is not likely the root cause of your issue now.

You're right. However i have noticed the flicker also exists if the engine is off and the lights are on, almost as if the left HID doesn't get enough power.