Key Fobs not working properly after battery was disconnected.

[aero_sport Lurker Find all posts View Profile Close aero_sport]

Hey guys,

Yesterday I installed new speakers and an amplifier in my 2016 GX Prado which involved disconnecting the battery the the factory radio.
Since completing the install, neither of my key fobs are working properly. I'm unable to lock and unlock the car, including the lock/unlock buttons on the rear door, and the only way I can use the push start/stop button is if the fob is basically making contact with the button itself.
I've hooked up techstream and had a bit of a look around there but it won't allow me to reregister the fobs or erase the current registrations to then try reregister them.

Has anybody experience this before after they've disconnected their battery or radio?

Any ideas would be much appreciated.

[Tripster Lurker Find all posts View Profile Close Tripster]

I'll watch this tread with interest. My locking system has started playing up also, why I'm here actually. Mine is intermittent, works fine then it doesn't. Do you get the "Key not recognised" (or something like that) warning? Sorry I can't help you, hopefully somebody can help both of us.

[Piggy Water pistol pilot. Find all posts View Profile Close Piggy]

Sounds like you've managed to unplug the near field sensor for the fobs located under the centre console. Or damaged something to do with the RF fob system.

[GeeWhizz Senior Member Find all posts View Profile Close GeeWhizz]

I'll watch this tread with interest. My locking system has started playing up also, why I'm here actually. Mine is intermittent, works fine then it doesn't. Do you get the "Key not recognised" (or something like that) warning? Sorry I can't help you, hopefully somebody can help both of us.

A bit awkward to answer this question here. My guess is that it nothing the do with the original post.

Start by replacing the battery in the key fob. My FOB battery only seems to last 5 or 6 months. When it starts to go flat, all sort of intermittant and inconsistant things happen.

[aero_sport Lurker Find all posts View Profile Close aero_sport]

Sounds like you've managed to unplug the near field sensor for the fobs located under the centre console. Or damaged something to do with the RF fob system.

I didn't touch anything near the centre console, but I am starting to think I've accidentally unplugged something.
I've gone back to basics. There's a 10a fuse under the dash for "smart entry & start system" and also under the bonnet there's another 10a fuse for ECU-B which the internet says is for "smart entry & start system". Both fuses have power in and out.
Next I want to check if there's a specific module for the smart key system and see if I've unplugged it accidentally, but I'm struggling to find where it is located. Again, the internet says there is one but not where to find it. If someone can point me in the right direction to find this module that would be great.
If that checks out fine then I'll be checking the the field sensors, which apparently there's multiple so if I've accidentally unplugged one then wouldn't the others still work?