ECU won't update, what could cause this?

Went to get the KDMax Tune and the tuner couldn't update my ECU. So I went to Toyota yesterday and after more than two hours they couldn't update it either. Said they were going to call corporate on Monday and get back with me. My convo with my service advisor went something along these lines.

Toyota Duder: So, we couldn't get it to update, probably because of all your mods.
Me: Which mod would block the ECU update?
Toyota Duder: I don't know, I'm not a service tech.

My mod list: My Daily Driver: 2019 Off-Road Cavalry Blue | Tacoma World

What on there could block an ECU update?

Also, I had a tuner try to update my ECU prior to the installation of the JVC Head Unit, Wireless Charger Mount and Heads Up Display and it wouldn't update. I bought the truck used and it had a Rockledge Securities sticker on the window (I don't know what/if any Rockledge products are installed on the truck, but there might have been at some point thus the window sticker) and an Alpine HALO 9 Head Unit preinstalled.

 

Or anyone have any thoughts on what would cause an ECU not to update? My truck aside, just in general.

*Edit*
Additional thought that I didn't want to bump my own thread again for. Toyota was going to charge me $200 to update the ECU, wouldn't this be covered under the 60 month/60k warranty? They told me this price prior to attempting/unable to update it.

 

ECU update is a TSB, it's free.

 

Yeah, TSB should 100% be covered.

 

My VIN doesn't show anything when looking on https://www.toyota.com/recall

 

It's not a recall, it's a TSB.

 

Pull your radio fuses and try again. You have aftermarket and those have been known to cause issues with the ECU.

 

Does your JVC head unit show OBD2 data? If so and not disabled...it will cause issues with flashing.

 

A TSB (Technical Service Bulletin) is not the same as a recall. It's basically just a document detailing a common problem or issue where as a recall is something that will be repaired regardless of warranty status. That said, a TSB may, or may not, be covered under warranty. It depends on the nature of the TSB and whether the vehicle in question is actually experiencing any of the problems related to the TSB.

 

My JVC does, the Alpine HALO 9 that was previously installed does not and it wasn't able to update when that was installed. I will ask them if they pulled the radio fuses when they give me a call this afternoon.

 

If the tuner is close enough, try again with the fuses pulled. No need to go to the dealership for that.

 

https://www.tacomaworld.com/threads/ecu-tsb-update.562550/page-11

 

See the Maestro spoiler in this post:

 

You guys are a life saver, gonna give this a go with the tuner and then report back.

 

They always blame the mods

 

I know this is their knee-jerk response to pretty much everything. So wanted to educate myself a bit on what the possible cause could be before I had a conversation with them. But with the info from @tonered and @ktbell444 I'm going to get back with the tuner to get the ECU update.

 

You also mention a heads up display. If this interfaces with the CAN, I suggest disabling it as well. Aftermarket traffic on factory CAN can make calibrations difficult.

 

Yeah it wouldn't update prior to the HUD but that can be unplugged easily enough.

 

Alright, so the OBD2 was already disabled.



After digging around I then found this:



So that would mean something is already connected thus disabling the OBD2? I have nothing connected myself (I wouldn't even know what to connect to where). I'm just trying to figure out what my ECU won't update and maybe whatever is connected already (where it would be connected is another question because if something was plugged in where the tuner and Toyota plugs into would have been noticeable).



And for good measure above is the OBD2 setting.

So to recap:
November 2020 - bought the truck from an out of state dealership (non-Toyota dealership out of Arizona), it had a dealer installed Alpine HALO 9 head unit and Rockledge securities system.
Spring 2021 - OVTuner had issues with it - I can't remember the exact reasons, but Shellshock had issues with my truck and it had to go last because it was going to take extra time.
Fall 2021 - had a new head unit installed, took it to a shop to get it done, they used the same hardware that was already installed with the Alpine (Maestro) as it had everything already (I bought a new set of everything from Crutchfield as I wasn't sure what was used on the installation of the Alpine unit, ended up returning it all since it wasn't used).
March 2022 - KDMax tuner couldn't get the ECU to update, I believe he even spoke to PapaRee on the phone when he was trying to get my truck updated. Suggested I take it to Toyota to get it updated.
April 2022 - Toyota takes 2+ hours trying to update it and they can't. They never get back with me on it after I have tried reaching out as a follow up.

Okay, so where do I go from here? Where do I start looking - either myself or what kind of a shop should I start looking for that can figure out what's going on.

 

Is it possible that the original OBDII plug has been relocated and has a jumper with a new OBDII connector in place for connectivity.

For example, the work trucks I use at work, have on board air systems, they use the OBDII to control engine function (RPM control) so the original plug is connected, buried up in the dash and a new plug is in place where the factory one was.