Uncommon Issue: Acc Mode On With Key Removed

[Arlo.]

I'm new here. I'm hoping one of you have the answer to this uncommon issue.

Yesterday I had my rotors, pads, and calipers replaced on my 2005 Sport V6. After picking up the 4Runner at the shop, the radio and light on the clock panel stay on with the key removed (they will stay on indefinitely, I had to just turn the power off the radio and hoped my battery wouldn't die overnight from the light). Basically, it's stuck in ACC mode with the key removed.

Today I talked to a friend who suggested checking the "ACC CUT" relay, so I checked it (with a new one) - nothing. Even pulled the relay out to see if it would change anything - it didn't.

Had the battery & charging system checked, they're working fine.

I then took it back to the shop that replaced the brakes. They've tried diagnosing the problem and are unable to find whats causing the issue.

My friend (who's a Toyota tech in a different part of the state) says the wiring diagrams show him that the ignition switch is what powers those items - so theres a chance it could be a bad ignition switch. He suggests unplugging the switch to see if it will turn off the acc mode. He said that the switch may not be the final problem, but unplugging it may be the next step to determining the issue.

Anyone have any ideas on what the issue may be? I appreciate the help!

note: I don't think this issue has any relevance to the brakes being replaced, but figured I'd mention it.

 

[Arlo.]

Update from Shop (still no resolution found)

Just got a call from the shop to pick it back up - they can't find the issue. They've tested the ignition switch and it seems to be working fine. They think it may be a corroded wire at the "junction connector" (he said it may be related to the BCM) which is apparently in the R quarter panel, behind the trim piece. He suggested taking it to a dealer.

 

[Arlo.]

Got home, took the knee panel out and unplugged the ignition switch - zero effect on the radio and lights.

I then took out the rear trim piece and there is no junction box there. Does any one know where the junction box is? I've not had any moisture in the interior since I've owned this 4Runner last June.

 

[Arlo.]

Just checked all fuses, none are blown (thought it may be a blown fuse causing the radio and light to pull from somewhere else)....

I have a suspicion about the aftermarket aux adapter... It's not working.

 

[Arlo.]

My suspicion about the auxiliary adapter turned out to be the problem. Somehow the adapter was drawing power to the radio. I could unplug the adapter and the radio would turn off (with key removed), and plug it back in again and the radio would power back on.

I could not find any visible issues with the adapter, but I still removed it completely. I'll have to do some research on other brands available. I bought this adapter off Amazon for $25 last year - used it all the time.