Does anyone know where I can find the truck's 3G/LTE module?

Brilliant!!! wish I had thought of that. I have mine un-plugged and fuse removed, and de-pinned the mic and speaker wires, then tied the appropriate wires together to make the speaker and hand free work again. to tie them together I simply wrapped tiny strands of copper, tight around the pins to connect them, and taped them. totally reversible, but removing the sim seems much cleaner.

 

Except there is soldering involved. Something most people will not attempt.

 

Any chance one of you really smart people could help show me which wires to connect on the dcm connector to retain mic on a 2020 Corolla?

 

I paid for AllData, for the wiring diagram. Plus I might not be one of the smart ones, it took me much study to understand the diagram.

 

I’ll gladly pay/buy whatever is needed. My dcm has apparently malfunctioned and I’m not willing to pay dealership 1000$ to replace . Alldata appears to be 20$. I’ll give it a look. Thanks.

 

So basically I need to connect MCI+ to MCO+, MCI- to MCO-, MCVD to 5v power (IG2 with converter to 5v), and SGND to ground to retain mic function? If I do use the IG2 connection with converter can I connect the SGND to USBG or do I need to do some other ground? I have found the diagram for my connector now. Thanks for any help!

 

Is the diagram for your vehicle the same as the one for our Tacomas?
See file.

 

Similar.

 

Well, according to the connectors in your diagram, the Tacoma 2020+ and your 2020 Corolla do not have the same DCM module. I was expecting Toyota to have standardized.

 

Yea the right speaker and mic are both on my main connector, so I’ll have to jump those sound/speaker wires as well. But I believe I can accomplish what others on this thread have done with the mic by matching the inputs with my connector.

 

Yes, the speakers are the easiest. On my vehicle the speaker wires are larger gauge aluminum wires. The ground can be practically anywhere there is an existing ground. But, just like your original post suggests the microphone is the problem.

In a cursory look over your schematic/diagram I was thinking there was no info on connector t1. USB?

 

Hard to navigate the techinfo Toyota site, haven’t found what goes to that connector yet-the other 3 are antennas though. I’ve decided to get a small converter and use IG2 but bringing it down to 5v to power mic. USB would probably drop too low under load. I’ll look a little further for what’s going on t1 connector.

 

The Toyota site should have nice color schematics available. I have never been on the site, my schematics came from someone on this site years ago. I will attach one below for your perusal.

 

if you are planning on leaving the DCM unplugged, you can jumper the terminals with a piece of wire, and do no harm. Otherwise you can carefully remove the retainer strip from teh

I believe you do not need the 5v. the mic is a coil, and the MC + & - will provide everything the mic needs. I am almost certain I only connected the two pairs, and my mic works great. The only thing I can think of that would need the 5v, is possibly the call button, for triggering for help, but not the mic.

Verify that you lost sound to the speaker, before bothering with those jumpers too; word on our tacomas, is that the speaker is still connected to the radio without power to the DCM; though this requires that the DCM connectors remain connected to the DCM box. Not sure how you plan to jumper, but be warned, much of the wires are aluminum, delicate and not solder-able. I decided to pop the keeper off the connector, remove the pins of the 4 mic wires, tie the pairs of "pins" or terminals with several tight wraps of a strand of copper from a larger wire, just a singe strand, and added some shrink wrap over the connection, so it can be reversed if needed, and no splicing or dealing with stupid aluminum wires.