Brake Pedal Causing Strange Electrical Issues?

So I'm not sure if anyone else has experienced this or could possibly shed some light as to what exactly might be causing this but..... On occasion (maybe a couple times a month) if it's a colder morning when I'm driving to work, hitting my brake pedal will reset my entertainment system? Yes I know this is strange but hear me out, I also notice that when I'm driving at night and my headlights are on, if I hit my brake pedal it will almost cause my headlights to surge brighter for a split second? I don't know how or if it's even possible that my brake pedal is somehow power surging something in the truck and that causes the entertainment system to crash and/or the headlights to get a jump in power but it's the weirdest thing and having my entertainment system restart 3-4 times within my 15 min drive to work in the morning is annoying and the whole thing just weirds me out. Any thoughts?

 

Only thing that comes to mind is leaking 3rd brake light causing power issues when activated? (Short)

 

The off-road has an electric brake booster... could be normalish?

For the radio, have you updated the radio software? There was an update to fix the rebooting issue.
https://securedp.toyota.com/download-app/downloads

 

It's only when it's cold? Could be the battery. Too much power draw from the brake booster and the voltage drops.... IDK though I'm just a shade tree

 

Is your truck bone stock?

G.

 

You have an electronic brake booster. Your alternator is going to have more load put on it when you step on the brakes. You’ll see the effect in your head lights. Your idle RPM will probably also go up. The ECM is pretty smart. As far as why your head unit is resetting, no idea.

A running vehicle doesn’t draw battery power. It’s running off alternator output. Batteries are for starting the vehicle.

 

The battery still serves to keep the voltage steady- the alternator doesn't instantly produce more power on demand. You would see much more dramatic headlight dimming and other electrical issues if you were run the car without a battery.

 

No. And that’s what a voltage regulator does.

 

A voltage regulator prevents overvoltage, not undervoltage. Read up on capacitors. Batteries are kinda like big versions of that.

 

I don’t even know why I’m bothering to respond to this given how completely false it is. But maybe you should go back and reread everything you think you know about basic electrical theory. A capacitor is nothing close to a battery or vice versa. Have a nice day.

 

Oh boy. what a thread.


All I can think to do would be to put a scope or maybe even a multimeter on it and see what the voltage is doing.

Spitball theory here is that something is up with your brake lights, and when you hit the brake pedal you're grounding out _something_, which is pulling down the voltage to the stereo causing hte reset, and at the same time providing a lower resistance path to ground for the headlights, causing them to brighten. But feels like a stretch.

Any other weird stuff going on? Maybe we should call an exorcist.

 

Does the truck have LED bulbs for the brake lights?

 

They both store electrical energy. They do it different ways and on different time/capacity scales, but they aren't completely unrelated. In some (very specific) applications you can certainly replace a battery with a (super)capacitor.

 

do you have Baja Designs LED lighting?

 

Check your battery, might be close to end-of-life. (Headlights will sometimes surge when the battery is not at full capacity.)

Also, this thread entertains, lol.

 

Looks like the OP is not answering questions about "Bone Stock", or installed LED's.

Hmmmm

G.

 

I have the exact same issue. Cooler weather and a tap to the brakes will cause the radio to blink / reset. I’ve looked all over for a short.
I originally thought it was an issue with my OEM radio so I replaced it with an aftermarket Alpine unit and it does the same thing.

With that said... the battery is low on life. I’m trying to decide if it’s worth taking to Toyota to have it diagnosed. I just worry they will look at my aftermarket head unit and wiring for the numerous lights and just put the blame there. When in reality it’s been doing this for several years. Way before the upgrades.

 

1. Any type of short, like water in the tail lights is going to blow a fuse before it shorts at such a load as to kill all power briefly. Think I'd lean toward lose ground wire here.
2. Vehicles will run perfectly normal without a battery. When charging, the battery is basically just a 30% resistance drain on the alt. Like if alt puts out 100 amps, only 70amps is actually stored in the batt, rest is heat loss in the battery. So disconnecting the battery actually puts less load on the alt.
3. I been running a capacitor instead of a lead acid battery for about 2 yrs. Beats lead acid in every way except for reserve capacity.

 

Not a short, it's voltage drop. It's a dying battery, loose battery terminals, loose electrical connection, or a poor ground.

 

I'm going to start with a battery... It's time.