Electrical situation.... looking for explination

DannyLlama

Elite Member
So... here I was in the middle of no reception zone in Sierra California and my 4R would shut off and allow for me to lock doors. After 20 minutes of freaking out, I unplugged a Traxxas battery charger from the rear cigarette lighter adapter and thats hat solved the problem.

The strangest part was that everything was shut off except my radio.

Radio on and car off, unable to lock up the car. Unplugged the charger and all is well.

Just wondering how the hell is that possible
 
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I'll take a WAG and say the charger may have been injecting harmonics that was interfering with other functions.
 
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Maybe something to do with your limited FOB / keyless system. The system might see that you're charging something off that circuit and not let you shut it down until you remove the load. Weird.
 
So... here I was in the middle of no reception zone in Sierra California and my 4R would shut off and allow for me to lock doors. After 20 minutes of freaking out, I unplugged a Traxxas battery charger from the rear cigarette lighter adapter and thats hat solved the problem.

The strangest part was that everything was shut off except my radio.

Radio on and car off, unable to lock up the car. Unplugged the charger and all is well.

Just wondering how the hell is that possible

I'm wondering if I experienced the same issue a few months ago. We have a few GMRS radios we take camping, but they died on us early (I think crap batteries). Luckily I brought the 12V car charger and docking station with us. First, I plugged in the charger to the cigarette plug within the center console while the car was on since we were driving - the radios charged fine this way.

After shutting off the car at camp, I tried to either lock or unlock the car via key fob and it wouldn't work. Thought the fob battery had died but the little red LED was clearly blinking with every click. After some trouble shooting, only after removing the radio charger from the cigarette plug was the car able to lock/unlock with the FOB. This same issue persisted regardless which cigarette plug I used, even the one in the trunk.

This probably doesn't help solve the issue - but know you're not alone with electrical gremlins/unknowns!
 
A lot of chargers use high frequency DC to DC conversion. I have a couple of cig lighter USB chargers that I can hear the high frequency if I get my ear near them.
I'm guessing that some of them put high frequency on the vehicle DC buss perhaps causing problems.

Side note- I have one of those inductive chargers for my phone mounted on the dash in another vehicle- worked fine for a year or more. One day I noticed I could not pinch the phone screen to zoom in and out on maps without it going nuts and zooming all over the place.
This went on for awhile until one day I noticed it was only when the phone was docked in that charger. Unplugged it and no more problems- now it is just a mount and I plug a micro usb cord in to charge.
 
It also might be that the charger generates radio waves that interfere with the fob signal. Can you lock the door with the door switch? Also I would try to power up the charger inside the vehicle with an external battery pack and see if it still disables the locks.
 
There's a tubeyou video staring a certain self promoting, retired mechanic with some nice sunglasses. Talks about "cheap" cigarette... I mean 12v chargers can play havoc with electronics. Something about the frequencies they put out.
 
There's a tubeyou video staring a certain self promoting, retired mechanic with some nice sunglasses. Talks about "cheap" cigarette... I mean 12v chargers can play havoc with electronics. Something about the frequencies they put out.

I love how he suggests you should get a cigarette lighter to USB adapter that's metal and only has one port, but I can't find any that have just one port these days. I had to get one that has two USB ports. At least I've had no problems with it.
 
The receiver for your fob is in the rear of the vehicle, other things such as fridges have been known to cause interference

I have no idea how that could shutoff your vehicle though
 
[MENTION=75328]DannyLlama[/MENTION]

I'm wondering if I experienced the same issue a few months ago. We have a few GMRS radios we take camping, but they died on us early (I think crap batteries). Luckily I brought the 12V car charger and docking station with us. First, I plugged in the charger to the cigarette plug within the center console while the car was on since we were driving - the radios charged fine this way.

After shutting off the car at camp, I tried to either lock or unlock the car via key fob and it wouldn't work. Thought the fob battery had died but the little red LED was clearly blinking with every click. After some trouble shooting, only after removing the radio charger from the cigarette plug was the car able to lock/unlock with the FOB. This same issue persisted regardless which cigarette plug I used, even the one in the trunk.

This probably doesn't help solve the issue - but know you're not alone with electrical gremlins/unknowns!

This exact same thing happened to me too! I can't help with the cause. I'm not very knowledgeable when it comes to electronics. But I plugged in my radios to charge in the back and it caused this exact issue and so they haven't charged back there since. I see you have a 2017 SR5. Did you do the mod to put in an older accessory display? I have a 2015 Trail but I put in a 2014 Accessory display and it was right after that I noticed this issue. Maybe about a year ago. I have no idea if the two could be connected. Probably not but maybe I should ask @OldRed
 
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I suspect what happens is the car signal from the fob is interrupted or the vehicle otherwise identifies a problem with the signal and thinks that it is stolen. The security system probably allows you to operate for a while without the key, but eventually will shut off the engine if the key is not recognized again. So that would explain why it randomly turned off. And probably when the vehicle is "off" the charging circuit in the rear isn't working, but as soon as it moves to accessory it re-energizes the system and then the device you are charging interferes with the key fob and it tells the ECU not to start the engine.

Just a random guess. But it could fit all of the symptoms and why you couldn't get past the accessory on condition.
 
[MENTION=75328]DannyLlama[/MENTION]



This exact same thing happened to me too! I can't help with the cause. I'm not very knowledgeable when it comes to electronics. But I plugged in my radios to charge in the back and it caused this exact issue and so they haven't charged back there since. I see you have a 2017 SR5. Did you do the mod to put in an older accessory display? I have a 2015 Trail but I put in a 2014 Accessory display and it was right after that I noticed this issue. Maybe about a year ago. I have no idea if the two could be connected. Probably not but maybe I should ask @OldRed

I've not done a mod to put in an older accessory display. The only electrical mod I've done so far is add a Switch Pros SP9100 unit - but I don't think that's what is causing the issue.
 
Many (most?) battery chargers are cheaply designed and don't use enough suppression or filtering so they generate all sorts of interference across the radio spectrum. Short of opening them up and using shunting caps and inductive toroids to filter the junk, you're going to have to deal with that.

Plugging them into the 12v system of the truck is essentially like attaching a huge antenna to it so it's not all that surprising that will then interfere with the relatively weak signals of wireless fobs.
 
Both of my fobs stopped working on Saturday and I had a semi glowing CEL. Wouldn't turn over - just cranked. Disconnected the battery and reset it. Turns out it was my Pedal Commander - had enough of an open draw to throw the code and kill the fobs. Fixed now though. But the fob thing kinda threw me.
 

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