ME-SO Map Light Install Issue

First off let me start by saying I had no issues at all with my map lights prior to the install. I also have the kit with the dome light. The dome light works perfectly fine.

Here’s my issue. When the truck is off they are super dim. I didn’t notice this when I installed during the day. This is a pic with the truck off. Main switch off. If I press the light to turn it on it’s full brightness.


Putting the truck into accessory mode or starting the light gets brighter. Again using the switches only makes it brighter.


If I press the switch they work fine and I go blind.


Has anyone seen this issue before? Any ideas? Switching the bulb adapter polarity just makes them not work.

 

So after reading this thread: https://www.tacomaworld.com/threads/dome-lights-wont-turn-off.402358/

I think I’m going to toss these in the trash and put my stock bulbs back in. The extra light is nice but not worth blowing $$ control modules.

 

Have you verified "all" the door closed switches?
Also, remove the center MESO LED lamp and verify the Maps still behave the same.
Donations accepted.

 

When you say verify all door closed switches you mean? The doors closed? If so yes. Truck started and seat belt on ready to go when I noticed they were barely on.

 

Can’t tell from the pics if yours are V2 with the red and white switch option, but I have recently installed them with no issues at all.

I have stock dome light at the moment.

Good luck,
Alan

 

Diode dynamics has a bright ass led pair of bulbs for $35 delivered.

 

If there's any rust behind the door closed switch location(s), the switch could be finding a path to ground even when door(s) are closed.

 

Wouldn’t this also affect the stock lights too though?

 

LED's require way less current than halogen ones. It's only a verification.
Somehow the MAP LED's are getting a ground - the fused feed is always ON.

 

You can typically unbolt the door switches 1 by 1 and see if the LEDs turn off. I’d probably actuate them by hand at each door and see if maybe one is stuck in it’s closed position. If the lights remain on, I’ve had body control module issues in the past on another Toyota that caused a grounding problem for the driver door, but that was a lack of ground, not a constant ground. But that thread linked seems to imply some people have had the opposite with constant ground.

 

Got it. I’ll go mess with it some more. Just have to wait for the rain to stop.

I know part of the troubleshooting is starting to remove stuff, but do you think the map light could be affecting it? It’s working and I’m scared to mess with anything in fear of frying ransoms control modules. However I don’t see how you can short out the map light.

 

Disconnecting the battery negative cable on the vehicle is first step for electrical work.
There are a few circuits that are always ON which when juice is disconnected they require initialization afterwards. And the OFF-ON to test is tedious during troubleshooting, so many skip it.
The simple task of removing and replacing a map lamp does not require battery disconnect, but many choose to remove the diffuser, reach in with a metal tool to remove the lamp, when pulling down the overhead console is what the required. Twist the lamp holder and remove with the lamp. Replace lamp to holder, insert lamp and lamp holder into hole in console, test then replace console to overhead location, no tools.

 

I didn’t disconnect the battery for any of it.

Mainly because the overhead console i just disconnected the main harness from the console which removed power as I was installing it. The dome light I didn’t because I couldn’t see any way to short it. I guess with the dome light I can see maybe I should have disconnected the battery but the console I don’t think there is a need - unless I am missing something.

 

Like I mentioned before, somehow the maps are getting ground when OFF and all doors are closed. ANd as you may see ILE would be the culprit. And for that to happen, an input is allowing the Main Body ECU to "activate" ILE terminal.

 

Okay. I’ll investigate a bit more.

With that said the dome light is also slightly illuminated. Does that change anything?

Also just to make sure I am clear. The lights aren’t actually fully on. They are just slightly on. In fact when in this state not all of the LED’s are lit up. I don’t know if that changes anything either.

Thanks for the help so far as well.

 

This diagram helped.

First off I hate modern vehicles and electronics. I have a dash cam that I wired up a long time ago. Guess what…besides always on and switched power I was using a ground in that main harness. Cut the ground, lights work fine.

 

Where was the ground tied to? The R44 connector to the overhead console has one white with black stripe. Where did you ground the dash cam?

 

The dashcam has three wires. One for continuous power, acc power, and ground. I can’t find a find a wiring diagram for the dashcam so I am going to guess yellow is acc, red continuous, black ground. Here is how I have them wired.

Red -> some pinkish looking wire
Yellow -> sorta brown
Black -> solid black. At first glance I don’t have a black/white wire.

Tomorrow I’m just going to run the dashcam ground into one of the metal roof brackets up there.

Excuse the dirty thumb. Here’s how I had it wired.

 

You are so lucky to not have damaged the circuits you are now using.
The ground wire on R44 is the end wire next to the black wire you thought was ground. It's in fact part of the overhead microphone amplifier. (MCO-)
The red arrow is pointing to the power to the differential lock switch. It should be slot #15 for always hot source. (overhead illumination source)
The yellow arrow is pointing to the another wire to the overhead microphone amplifier (MACC)

 

I’d say.

It was back before I knew how these trucks were wired. So I just busted out my multimeter found what I needed and went to town.

With that said, are there any wires off of that connector I can safely use for always on power and acc? The ground is easy. Or should I just remove the whole thing I run from the fuse box or somewhere else?