Heat seats stopped working

Hi,
I have a 2016 sr5 and just installed a hamilton t10 head unit. Everything works great and i’m happy with it (excepted the microphone quality is pretty bad) but now both of my front heated seats don’t work. The light on both switches doesn’t even turn on. I tried changing both the 20a and 30a fuses for the seats under the steering wheel and that did not fix the problem, and the fuses looked fine. Any thoughts would be helpful on possible fixes. thanks in advance.

 

Welcome to the forum from North carolina.

Did every connector get plugged back in after installing the new head unit? First thing I would look into being that parts would have been needed to nbe removed during replacement.

 

Welcome.

Not sure why you would unplug the seat switches or seats to install radio. If you didn't disconnect the battery during install, go through EVERY fuse under the dash. You never what controls multiple things for some reason. And make sure ALL connectors are plugged in correctly behind the radio. No bent pins or harnesses got cut or torn. The seat harness runs on the floor up to fuse box in the dash. I've done crazy ass things when crawling around installing things.

And run an external mic. Those built in ones suck.

 

Welcome

 

welcome

 

I did forgot to unplug the battery during install. everything else works great. I will check every fuse under the steering wheel. I assume just pull out one at a time and put back in if it looks okay.

I didn’t unplug anything seat related and everything that had a spot was plugged back in. plus not sure why heated seat controls would run through the head unit??

Any recommendations on an external mic and install?

thanks everyone

 

Correct. Just pull the fuses out one by one and quick glance while the truck is off.

 

Some guys won't take their truck to a shop for an oil change because they are afraid a high school grad will damage it.

Yet they will tear into the electrical system, the most complex system in a 4Runner, without any knowledge, thought or idea about what they are doing...

Funny, huh?

 

Did you cut into ANY wiring harness for the install, or did this come with proper adapters?

 

I just installed a Kenwood Excelon HU in my 2011 Limited. The great thing about it was I ordered everything from Crutchfield and got all of the necessary adapters. I maintained all functionality of the OEM unit and didn't need to cut a single wire. There's absolutely no reason to cut into ANY harness. Anybody that does so is a fool.

 

Amen to this. I always laugh when I see people who barely graduated high school tear into a complex electrical system & wiring diagram.

Some people have too much pride & ego.

 

Here's the diagram for the heated seats. Chec both the 20A Seat Heater FR and the 10A ECU-IG No 2?Next thing I would check is the heater control sub assemblies under the seats. Did both seats stop working simultaneously? To me that seems odd that they both quit.

 

He's got something unplugged or disconnected somewhere.

Looking at EVERY fuse in the fuse box is a waste of time. And fuses are properly tested with a meter.

In addition fuses don't just "blow". There's a reason they are called overcurrent devices...

 

When i was in junior high, i was the family electrical/electronic sme. Lol. Had to always set up the entertainment centers and run the electrics so it didn't overload. Cuz my parents didn't understand that new fangled vcr and component stereos. Lol

 

Cat, well said. I'm a retired electrical engineer. When I replaced the OEM head unit in my 15 SR5 I studied the Crutchfield instructions until I understood them completely. And I ordered the right harnesses to insure I would do NO CUTTING.

After I understood the process and the instructions I went to work. It took me less than 3 hours to R&R the old unit and install my new Kenwood unit, a microphone and an I-Data Link. Plug and play was easy peasy because I made sure I understood what I was doing. And everything worked just as it was supposed to.

I get a real chuckle out of these jake-leg shade tree mechanics looking for someone to bail them out.

I don't reply to electrical posts with help, although most of these "problems" have simple solutions. How else are those guys going to learn not to mess with stuff they don't understand?

 

No cutting of any kind happened. even when the seats are turned on, there is no light that goes on anymore

 

Ok.this is good information. Don't know where your expertise with electrical stops, but that switch in the center console is super easy to pull out and get a multimeter on. Or at least a tester that lights up when there's power. That will at least tell you if power is getting to the switch and maybe the switch happened to quit by coincidence.

 

This may seem like a stupid question, and it isn't meant to be insulting but are you 100% sure the heated seats worked before you started the head unit/wiring project? When was the last time you used them?

Maybe the heated seats not working is un-related.

 

"coincidence"?

In the words of The Duke, "Not likely"...

 

I bought a used 2021 SR5 Prem. and neither seat heater worked.
The seat heater control units under the seat are known to have problems.
There can also be problems with the switches on the console. The switches are located where it's easy to spill something on them.
I pulled both the switches prior to replacing the control units, and cleaned them with electrical contact cleaner. That didn't solve the problem so I replaced the control units, (about $110 each from the dealer), now they work fine.