Key Fobs no longer recognized after new Main Body ECU Installation

Just replaced my Main Body ECU to fix my fuck up when the installation of my LED dome light went bad and fried the Overhead Console AND the Main Body ECU that controls a shit-load of stuff like interior lights, anti-theft, the list is too long. All I know is I am indebted to @caribe makaira for his incredible support and knowledge. Dude's a frikkin' national treasure....make that International!

LET THIS BE A LESSON TO THOSE DOING EVEN THE SIMPLEST ELECTRICAL FUCKERY WITH THEIR VEHICLES!
IT'S NOT 19-FUCKIN'-80 ANYMORE!

DISCONNECT YOUR BATTERY!!​

After replacing the ECU, everything is bitchin! Everything that DIDN'T work now works. Test drove after installing the new Meso light and the new footwell lights and life is good. Went in for the night and pushed the button on the fob and......silence. Neither Fob works on the truck. Yes, they are good. I believe the fobs no longer recognize the truck...or actually the other way around. I assume the signal might be different from the truck.

I'm thinking this might be remedied by reprogramming the fobs like they are new but I'm JUST stabbing a guess. The little red light on the center-dash flashes continuously even when the fobs are in the vehicle. Late last night I perused a couple videos on U-toob and did see a company that will send you an OBD module that allows programming, then you send it back for a refund. I'm going online to sponge some outside info on that possibility but I'm wondering if this might be a TechStream exclusive. I know there's a couple-a-few TechStream gurus around like @tonered and others I forget off hand. I wouldn't mind some guidance on actually obtaining TechStream, as well since I plan on being buried in this Taco, preferably while it's running. Same for the RAV4 I'm about to buy for the wife. She'll have to figure out the burial process, though. It seems like a smart investment.

 

I'll second your guess, you probably have to reprogram your your key fobs. I haven't priced those modules bu I doubt if thay are expensive.

 

Modules? Do I need more stiiiiiinking modules?!

 

Maybe double check your connections. I don't see that replacing the main body ECU requires registering new key fobs (assuming you're PTS).

 

Yes on PTS. I 'spose that's a good start. I'll go and give that a shot. I operating under the premise that the ECU contains the code or frequency or ?? that the fobs must produce making it different from other vehicles. Again, assuming this because this ECU is responsible for Alarm, anti-theft functions. I could be way off on this, obviously!

 

To start with, need more info on what exactly works and what doesnt.

If it PTS, the truck has to recognize the key to allow starting the truck. Is that working? Pr does it only start if you hold the dongle right up to the start button?
Will the dongle unlock or lock the keyless entry on the driver door (not the buttons on the key)
Sure you don't have a dongle left in the truck?

(BTW, it sounds like maybe the truck has just forgotten the remote buttons on the key, assuming the truck starts then the security ECU still recognizes the key fobs....

 

Replacement of the certification ECU is what would warrant registering key fobs again. At least from what I could tell.

 

Interesting. Thanks for the schematic. I'm about to go check connections. Junction box connections might be tough to have in wrong as they're tip out, locking module type connectors. There are 2 pretty chunky single connectors on the face of the JB, down low and side by side that look like a LAN connection or phone connection on steroids with a single fat cable on each. I'm going after those first. The Certification ECU went untouched in this process as I disconnected all the connectors from the JB to pull it out, separate the MBECU and replace, then put back in. Anyway....off to check connectors to see what happens.

 

You need TechStream, Dealership @$$1$TANCE or keep guessing

Door Control ECU talks to Main Body ECU which Network Gateway manages and receives input from door handle antenna, etc, etc..

 

If you keep laughing at me, I'm gonna start calling you in the middle of the night looking for more advice! And you're right again...I DO need TechStream. This string of fuck-ups will continue until morale improves.

@BigWhiteTRD Sorry, your post slipped in between my views.

The good thing is the truck starts so the system MUST be recognizing the chip in the fob. This is just with the fob in the truck, not being held up to PTS. The door touch buttons on the handles do not lock or unlock the truck. I have to use the key. The push buttons on the fob all activate the little red light on the fob but the truck does nothing in response. Aside for those issues, everything else functions regarding the interior light system that didn't after my handiwork of frying. I cannot identify any other systems that don't work. It seem to be exclusively the fob.

 

Interesting

So the PDF of the repair manual (for 2016) has this note about 100 times, but as its a dumb pdf its not linked to read more details on the note.
If it were I, I would get the short term TIS service now.... so I could figure out what instructions this is trying to tell me. (I will keep looking for now, but no guarantees)

 

So still trying to wrap my head around this, but it looks like the Main Body ECU receives the wireless door lock/unlock signals when you have a normal key, and the security ECU does it when you have a PushToStart.



Note, I still cant find the instructions for when you replace the Main Body ECU (in teh pdf)

 

Look up REGISTRATION on the repair pdf...

 

Getting somewhere. I just ran my OBD Scan tool (limited) Carista to do an ECU info scan.

On the systems I recognize as being MBECU related, it shows "ECU not present" like it doesn't see it. Not sure if that's related but maybe this idea of "registering" the new unit is on track.

 

Attached

Good job finding those notes, I didn't see them anywhere in my RM.

 

Fuckin Aye! That's Gold!

Gotta study that now. Maybe something I can't do, unless I have the TechStream or go to the deale..........oh GOD, I can't say it!

 

Your milkshake doesn't bring anyone anywhere...

 

OP, I'd say go to place where you bought the Taco, and improvise a story of how out of nowhere the fobs won't work. That you suspect they have lost REGISTRATION with the vehicle, that you read it in a Forum. (So they they will know they can't easily take you on a dead end street.)

 

Like I should have done from the very beginning?