Stuck in diagnostic mode when driving

I had my car detailed today, and when I went to pick up the car, it was already on and in the diagnostic mode menu. I didn't really think anything of it and figured maybe they were just checking things for whatever reason.
I drove it home without restarting the car, and it was in diagnostic mode the whole time, with various dash lights blinking (pretty much all of them, ABS, VSC, tire pressure, check engine, airbag, etc). It basically constantly cycled between a diagnostic mode menu (the screen that has the option to clear memory), the start screen that says toyota, and the map. It would stay on each screen for maybe 5-10 seconds, then move to the next one.

About 1/4 mile from my house I got the red triangle ! and the ! red car. I figured it was probably just an issue with driving in diagnostic mode. So I got home, turned the car off and back on, and it got out of diagnostic, but the red triangle and red car symbol stayed on.

I disconnected the trunk 12V to do a reset of the computer. This fixed the red triangle and red ! car symbol, but the diagnostic menu cycling issue is still there.

It only happens when the car is moving. If I start it, leave it in park, even change to neutral, drive or reverse and keep my foot on the brake, it's fine. But as soon as it starts to move, all hell breaks loose.

I looked at the error codes and there were multiple errors for DSP-AMP, navi, EMV, and audio. Mostly no/bad electrical connection errors (power source circuit errors/electrical harness according to the code guide) to MFD, audio h/u, navigation and XM.

So far, I have pulled the MFD out and did a visual inspection of the connections to it. No visibly loose wires or connectors. I didn't have a multimeter, so no electrical testing. After pulling it and checking it, and also pulling the white connector next to the trunk battery, it did resolve for a little while. But I took it for a test drive and about 2 minutes in it started up again.

I also checked the battery on the diagnostic screen and it appears to be fine.

So, any ideas? It seems like it's a connector issue, but I'm not entirely sure why it only happens when driving. Maybe increase in voltage from the car running harder? I'm not really sure how the detail could/would have affected the electrical though. They did say they did some sort of A/C cleaning type thing.

The most common flickering dash light is the tire pressure. So I'm also thinking maybe something they could have done to the TPMS when cleaning the wheels? Is that even possible?

By the way, I will be calling/going back to the place where it was detailed tomorrow. But hoping to be able to fix it on my own to avoid any headache of them refusing to pay, etc.

 

So it appears to have sorted itself out as of this morning.

They did a steam cleaning of the interior during the detail yesterday, so my only guess is that perhaps some steam condensed on a connector somewhere, and was causing a short. Still not entirely sure why it only happened while the car was moving.

I haven't been in the car today, this is all reports from my wife. Another possibility I've thought of is maybe a connector coming a little loose under the seat while they were cleaning (although I think the audio is under the passenger seat, not the driver...), and since she has the seat closer, it's not straining the connection. This also doesn't really account for the issue only happening when the car is moving. Going to check on that when she gets home though.