Simpler solution for disabling the DCM telematics - Silencing Antennas

Removed the "suspected" SIM as shown in post #111 and TechStream no longer sees the module as active. I will watch the DCM display on the radio when I get a chance - dash is apart at the moment doing other mods.

 

Finally getting close to doing this!

best video i found on how to take apart to access the box to cover in foil and fakra-resistors combos

https://youtu.be/V0LdhmlkhPY?

 

Interesting, where is the DCM fuse?

I have an aftermarket head unit with its own microphone, so i would bypass the microphone issue with no extra effort. Edit: sony trailgridpro bundle, if anyone wondering, comes with a piece of plastic to mount the mic hidden centered inside headliner plastic lights and other stuff thing, next to sunglasses case/emergency phone button thing.


My status:
I just jumped back in here wondering if my foil wrapping was sufficient, and was disappointed to see it was not that easy; i think i accidentally unfollowed the thread and saw the updates from those with better radio knowledge and more intrepidness - and i thought i was almost done with others having bravely gone before me to work out all the tricky stuff. I did break one piece of next to a trim clip connecting plastic, but i think i’ll be able to glue it back together with some additional hdpe from a 6 pack ring and construction adhesive so it’s not visible.

 

Soldering new bypassing wires to the right side speakers or whichever ones depend on this connection to work not be too bad if someone else figured out what wires to connect where, and where/how to access, might be able to just use t-taps or splice in with wagos, and between 1 to 3 (for the 3 right side speakers) new wires or wire sets.
It occurred to me that all the oem speaker wiring could be bypassed with an aftermarket head unit, but that’s a lot of work, also not sure if using the original wiring for driver side, and the rca outs for the passenger side would make the sound kinda off or out of sorts.

 

DCM fuse: where is this located? Are we sure pulling it doesn't result in any error codes? Some codes seem to take a while for the obd to pickup on.

Black connector: what is the name or original purpose of the black connector below the three antenna connector we capped with the fakra resistor assemblies? I don’t want to leave this area open too long, since i can’t drive it and could forget how to reassemble, so i may copy disgruntled scientist’s config and close up for now.

 

DCM fuse is in engine compartment fuse box.

The small black connector under the three antenna wires is a network connection to the radio.

In all my fooling around with the DCM I have had absolutely no codes come up. Techstream may see them, but with a regular code reader I’ve seen none.

 

Network connection to radio as in head unit, AM/FM, wifi, something else? What kind of radio /what does Toyota want it to do?

Is this a good diagram to follow for pulling the DCM fuse? Found via image search, and never done before

 

The fuse box has all the fuse and relay locations on the inside of the cover.

The network connection from the DCM goes to the back of the radio/head unit above the environmental controls. Not sure what it does.

 

I hope not to do this more than once, though i am impressed that the leaders of this thread were able to take this annoying part in and out multiple times for us.

so far this is what i have gathered, and i hope someone will chime in with some additional clarity.

A lazy look at patterns and codes in search results about codes for an ICCID or IMSI results strongly suggests the suspected SIM was the actual SIM.

i imagine the built in battery on the module will die eventually, just like a cell phone battery that does not get charged would, if the dcm fuse is disconnected, or replaced with a blown fuse? Will some kind of failure code present after dcm battery death?

it seems like the most complete taco internet disconnect so far without coding or getting error messages is just:
- 3 resistor cap fakra assemblies
- full foil wrap, doubled, with insulator between layers
- disconnect black cable below 3 fakras
- pull dcm fuse at fuse box located under the hood
- desolder and remove soldered in sim card

i am not entirely sure which combos of these steps are or are not redundant, and have been tested long enough to know they won’t annoy you with errors, and/or if anyone is still working on a better complete de-interneting method, like removing dcm entirely, while maintaining speaker functions and avoiding error codes?


Has the OBD / Techstream tools remained error code free?
I still have everything open but and don’t think i want to reopen again later, so considering also removing the sim from the board. I was able to run camera power and mic wires behind the glove box area while it is all open. Plus running power for a subwoofer and installing front camera while everything is open. I don’t really like pulling trim off, so the fewer times i have to take apart stuff the better.

 

Just to be clear as to how this thread got so off track with so many options and confusion. The OP (and I) thought that disconnecting and terminating the DCM antennas was a much more elegant method of disabling the DCM than what had been developed in the previous threads. I believe in cutting the head off of what I wish to kill - just seems easier than cutting off every extremity. My attack upon the “suspected” SIM card is just a continuation of that thought, I do not recommend it to anyone due to the very specialized nature of soldering surface mount components; electronic hobbyists go right ahead. De soldering the suspected SIM was much easier than I thought - all it required was a heat gun to melt the solder and the chip slid right off its solder pads.

@MattiasdelTaco
If you do not need to use the stock microphone, just remove the DCM fuse - that should be all that’s necessary; no power, dead DCM, no transmission to Toyota. Check to make sure your driver’s side speaker(s) still work and you’re done - there is some discussion as to if it is the door or the dash tweeter that doesn’t work if the small 4-wire connector on the DCM is disconnected. My thinking, it is both the door and tweeter, as there are four wires to the tweeter and then two go on to the door speaker, or I so suspect.

My current configuration is:
1) SIM Card removed - not necessary!
2) DCM Fuse removed.
3) DCM 4-wire Speaker connector plugged in - very necessary.
4) The three antennas are not plugged in and they are not terminated either as with no power there will be no RF Power present at anytime. Not necessary to unplug or do anything with them with the DCM Fuse removed.
5) Small black network connector not plugged in. Not necessary either.
6) Large main black DCM connector not plugged in - I have no interest in using the microphone. This is not necessary to remove either as again there is no power to the DCM.
7) A lot of what I have unplugged is just in case someone replaces the DCM Fuse without consulting me.

The only things that are necessary for me is to keep the small white 4-wire speaker connector plugged in so I have left channel front audio ( rear audio works in any case) and the removal of the DCM Fuse.

No codes are shown either using a run-of-the-mill code reader or within TechStream, but TechStream cannot even see the module - so there could possibly be a code if it was ever brought back to life. Another reason for all the unnecessarily disconnected connectors.

 

I wish there was a microphone bypass... I use hands off phone all the time.

 

If you’re ready to say goodbye to the oem head unit, this is just as clean. I routed the cable the other way, since i had passenger side open for the mods in this thread.
https://youtu.be/X5_02EtAWko?
For a while i was using the Sony mic in about the same place, or fallen down, but wires out, and it worked fine.

 

If you're not afraid of de-pinning DCM harness, there appears to be a way to disable the DCM and maintain mic w/ stock head unit. Check out this thread -- https://www.tacomaworld.com/threads/disabling-the-dcm-not-another-tin-foil-thread.825734/

 

Thank you both.

 

This is way more work than I think most people are going to be comfortable doing on their own vehicle. I don't understand 98% of the words being used in this thread related to electrical parts of the vehicle. I'd rather just pull the DCM fuse, but it's ridiculous that the right hand speakers are wired to the DCM.

This will probably be the main reason I don't buy a '24 Tacoma. Hell, it was why I passed on the GX 460. Built in FORCED internet connectivity that can't be easily disabled, you have to do some sort of electrical work just to "recover" your speakers. Jesus.

 

I installed a new head unit and I did a proper installation. Meaning, I didn't use any factory wires. I ran 3 sets of RCA's (front,rear,sub) to an active EQ, then RCA wires to amps for the front, rear, and subs. I ran new 10ga speaker wires from the amps to each door speaker

The only Toyota wire connected to my head unit is the one for the GPS

My question is, can I just remove the whole DCM module and toss it in the trash? Would it effect any other systems on the truck? Will the GPS antenna still work?

I don't mind running a new GPS antenna if need be.

Side note, my degree is in computer science and way back was really big into programming cell phones, has anyone tried looking for a service header on the PCB so we could just connect to it and 0000000000 out the IMEI? Or I noticed there is only a few leads coming from the cellular radio CAN. Why not just cut those leads or remove the resistors and diodes on the leads connecting the CAN to the PCB?

 

Based on my read of everyone else’s posts in these threads related to the dcm, i think given your rewired speakers, you would have no issues removing the dcm entirely, but it might throw a code or error of some kind eventually, though, no one has reported any that matter or that appear while driving, maybe in techstream though. Garmin makes a tiny bluetooth gps that integrates easily to give a phone or tablet more accurate location.


How hard was it to run new speaker wires to the head unit?
[I considered it, but not sure how long it might take? Is it really noticeably better, in any ways, or do you think you just did it cause you wanted to? My hu does have rca outs, but i was only planning on using the subwoofer rca out, as rewiring speaker wires too seems like a lot of work.

What are your thoughts on the likely audio characteristics/results of using original wiring for driver side, and the rca outs for the passenger side? No separate amp.

 

Anyone have a copy of the disclosure agreement? It should list the provider being used, I think it's ATT. Could just call and request they blacklist the IMEI?

 

I did the same setup on my 2nd gen. It's a bit of a pain, you have to remove the door panels and the inside panels and unplug the ends of the rubber boot with the OEM wires coming from the door and fish the wire through. Use a sort of stiff single wire like thin power wire to fish the wire through then pull the speaker wires through. If you don't want to do that, open the door panels note the color of the speaker wires. Pull the inside panel and look at the wire cluster. Find those wires inside the cab, they are easy to find because they are twisted together, then cut the wires right there and run the wires to your amps. There is always a grey negative wire and a colored wire twisted together.

https://www.tacomaworld.com/threads...3rd-gen-today.399305/page-13824#post-29614087


https://www.tacomaworld.com/threads...3rd-gen-today.399305/page-13828#post-29617263

I ran the RCA's under the carpet to the x-over, then the RCA's from x-over under the carpet around the back of the console. I ran the speaker wires under the carpet to the 4 channel amp under the driver seat. Forgive the messyness and the white label tape, that was work in progress.

It is WELL worth doing! Sounds 20000x better than just installing a new head unit!!!

 

check out this post on a Bronco forum about this, wonder if we can call Toyota and get all of the info on the cell modems?

https://www.bronco6g.com/forum/thre...t-t-to-t-mobile-almost-there-need-help.50157/