Doors locking randomly

That is an aftermarket alarm remote control. It's made by Karr. Most likely model 4040A. The install and programming instructions are in this thread, posted by me. The control unit is most likely in the driver's kick panel. However I would definitely look very closely at the remote control (as I previously wrote to you) first. 95% of the time the problem you described is in the remote control.

 

This may have already been covered. But if you unlock the doors with the key fob but don't open a door....the system will relock the door and flash the lights and beep 30 seconds later.

 

My FIL always kept his keys in his pocket. Sometimes, especially when he was sitting down, the unlock button would be pressed accidentally. 30 seconds later the lights would flash and beep. Sometimes he would see or hear it. More than once he called me to tell something wasn't right with the van.

 

Women, purses, and alarm remote controls are notorious for what you described.

 

Yep.

He had an '04 Sienna with the same key fob we have. He would say this damn thing beeped and flashed again. I would remind to take his keys out of his pocket. Probably happened 5 or 6 times over the years.

 

Seriously I don't think that is accurate. The image he posted looks identically to mine which is a Toyota factory keyless FOB. It also looks identical to my wifes 2010 Highlander FOB which is also factory Toyota. Made by TRW and used by many auto manufacturers.

Neither of us has an alarm system of any kind installed. The 2010 Highlander only has the chipped key and the Tacoma has nothing except the Smithfield Arms Range Commander 9mm security system.

 

Hey been in Montana for a couple days now and just returned to this thread! Thanks for all the info but there’s some stuff I want to clear up! It’s not just when the car is parked and off that it locks, it’s also when I’m driving, actually mostly when I’m driving and the truck is on. Sometimes it will be one every couple seconds and other times it will lock once every couple minutes. On some rides it does both. But my truck still locks itself even when the fob is out of range so it has to be something with the truck. Maybe a fuse? I have no idea...

Sorry lol I didn’t see the message I have really bad service out here!

 

oops sorry i guess they are different. heres mine

 

Here's mine

Mine is a Karr 4040a.
It is aftermarket.
A dealer installed alarm that can be hooked up as a keyless entry only.
It is NOT factory.
Technically it's not even dealer installed as wholesale installer companies are sublet to do the actual work.
Karr is made by Prestige.
Prestige is sold by Audiovox.
Karr was only available at car dealers when I retired.
Prestige was only available for retail sale when I retired.
I have 36 years of professional and continual experience in the automotive security system industry (among many other trades that are often split up).
I have installed thousands of car alarms and keyless entry systems.
.
My friend Scott has been installing Karr for over 15 years.
.
Have a fantastic weekend.

 

I'm missing some information so if you start reading a paragraph that doesn't apply to your situation just ignore that paragraph..

"But my truck still locks itself even when the fob is out of range...". Do a test: unlock the truck with the remote control and do not open a door, if it locks itself appropriately 30 seconds after you hit the unlock button that is called passive arming/locking. It is a programmable feature (it can be turned on or off). Programming instructions are in the owners manual that I posted the pdf file of in this thread.

"But my truck still locks itself even when the fob is out of range...". If it is locking the doors at completely random times while it's parked then there is a part failure somewhere which I will get into a little later down this comment.

I know everything there is to know about automotive security systems but
@Muddinfun
knows a LOT more about Tacomas than I do and he suggested that it might be the electrical switch that is on the driver's door lock inside the door.

To me it sounds like all of your issues are the same problem. It doesn't sound like you're having a problem with the doors unlocking randomly - only locking randomly. The first place I would personally go look at is the door lock relay. Your truck has factory door lock relay and when an aftermarket system is installed an aftermarket relay is not required so your truck shouldn't have them. Find the factory door lock relay, I'm exhausted otherwise I'd find it for you. If the door lock relay is separate from the door unlock relay swap the 2 relays and see what happens. My guess is that it'll start randomly unlocking the doors.

If your system is wired up as a keyless entry and not as a full alarm it's possible that it's losing power or ground because whenever it is first powered up it does lock the doors. If it were a full alarm it would also sound the truck's horns and I'm sure you would have written that if that has been happening. So if it's a loose connection it would just keep locking the doors every time it made a connection.

I'm losing my train of thought, I'm really tired. Let me know OP if any of this helped/need more info.

 

That did help, I know about the passive lock thing but I’ll just be sitting in my garage and all the sudden my truck locks itself and I’ll see the lights when my keys are in my room lol. You are correct when you said they only lock, they never unlock. Also recently my lock buttons on both driver and passenger doors have been not working randomly mostly when the truck is off. Great info man! Lmk what you think

 

There are no relays for the door locks. They’re all controlled by the body ECU. The door key locks, the door panel switches, and the keyless entry module all send a signal to the body ECU and then the body ECU powers the lock motors to lock and unlock. I still strongly suspect the key lock switch. The best way to confirm that would be to unplug a few switches and see if it still locks. Starting with the door panel switches would be the easiest. Then move on to the door lock switches which would require removing the door panels.

https://m.youtube.com/watch?v=yjhYKzE_yBg

 

I looked up Tacoma second gen aftermarket alarm wire location pick up points and it's a negative pulse to lock or unlock which means somewhere there is a pair relays, they must be inside the body control unit, or inside the ECU. Either way it doesn't sound like their an independently serviceable part.

 

It really sounds like there's a bad aftermarket relay that's going out but Tacomas don't need aftermarket relays for the door locks so there shouldn't be any in your truck.

The truck locking the doors and flashing the lights when it is not running is definitely passive locking, the difficult part is why it's doing it at random times.

Does the dome light work correctly? Any issue with the dome light, the dome light circuit, or the door dome light switches thart are in the door jams?

When you're driving the truck and it randomly locks does it also flash the parking/dash lights?

IF you've had the driver's lower dash off and the kick panel off have you seen Scotch Locks? Scotch Locks look like this:

They're horrible connectors and notorious for causing weird connectivity problems. edit: the one in the upper left corner of the picture is a T tap, when the correct sized T tap is used I've never had a problem with them.

I think you should try to find the keyless entry control module and you should unplug the door lock output and drive the truck to see if the random locking while driving stops. It's most likely in the driver kick panel but could be underneath the driver's side of the dash. The door lock output out of the keyless entry are 2 wires, a green wire and a blue wire, they're in their own plug, and the wires themselves are very small (22 gauge). Once that door lock output plug has been unplugged the locking system is stock at that point (assuming it doesn't have aftermarket relays for the door locks) so the results will dictate if you're having a factory Tacoma problem or an aftermarket keyless entry problem.

This is what the keyless entry control module looks like, it's about 4"x4"x1".

Once you find the keyless entry control unit and that door lock output plug you could follow those 2 wires to their connection point and make sure it doesn't have aftermarket relays for the door locks because it still sounds like an aftermarket relay problem to me.

According to my phones navigation you're city is 69 miles away from me, 1 hour and 15 minutes away at 3 AM, lol. I love challenges that make me think and that are in my former industry, other than parts I'll fix it for free if you bring it to me. I'm 100% positive I could figure it out if I got my hands on it.

 

Keyless entry doesn’t work when the ignition is on.

 

Sorry OP! I’ve never had problems with my Amazon key fob with factory key. You reprogram them yet? Or get a new 1?

$13 Key Fob Keyless Entry Remote fits Toyota Tacoma Tundra Sienna Sequoia Highlander (GQ43VT20T 3-Btn)

https://www.amazon.com/dp/B06XRGT7W1/ref=cm_sw_r_cp_api_i_6AWMEbNHT9TX2

Price has increased but I paid $11 for mine. I’d try that first.

Also thanks for the video!!

 

Correct - assuming it has a good connection to the ignition.

 

By “it”, you must mean the body ECU. If IG1 NO2 is not supplying power to the body ECU, you’ve got lots of other problems.

 

I am fairly sure you're referring to a factory keyless entry system and I was referring to an aftermarket keyless entry system.

 

OMG! Who wired that rats nest. I hope that isn't your work.

They should be ashamed of themselves and go back to being a custodial engineer.