LewisLou

Mesquite77

I would use a volt meter and probe at the connectors. This way you can test if it is switched or not, and there will be no guessing. $5 gets a multimeter, useful for kinds of stuff.

DennisMik

According to my schematic, the plastic wire connector has 7 positions and 4 wires. All the wires show as black. Pins 3 & 4 are the mirror input/output signal(s) and pins 6 & 7 are the power. Pin 7 is the 12 volts to the mirror and pin 6 is the ground.

LewisLou

mnewxcv

what is the fuse rating for that circuit? Wonder if it can power my radar, GPS, and dashcam.

DennisMik

The fuse on that circuit is 7.5 amps. That fuse powers more than the rear view mirror, it powers the body ECU and probably some of the stuff in the overhead console. Unfortunately, Toyota wiring diagrams do not tell you everything that a fuse powers like other car manufacturers.

But I doubt that you can power the radar, GPS, and dashcam from the mirror power. While the fuse should not have a 7 amp load on it, I don't know if there is enough reserve for the Items you mentioned. When you ask questions like this, it would be helpful if you tell us how many amps the extra equipment will take. I would guess that the radar, GPS, and dashcam probably need 4 to 5 amps. As a second reason as to why not, the wire going to the junction block for the mirror is pretty small and probably can't handle 4 additional amps.

There is a 30 amp fuse for the sunroof and you could consider that but the drawback there is that it is hot all the time. You have to remember to turn all the devices off when you park the car of you might have starting problems in the morning. I don't recommend it.

mnewxcv

Thanks, the devices should total around 4 amps. The sunroof uses a relay if the 30A circuit is always hot then? I should look this up myself, but I am kind of thinking out loud. If I used a relay that tapped into the 30A sunroof circuit, and it was triggered by the 7.5A mirror circuit, it would utilize the larger wiring/circuitry and not worry about overloading the wires or circuit, and it would be switched with the key. Just need to figure out of there is room for a relay in there.

DennisMik

There is no relay for the 30 amp sunroof fuse. Since the sunroof and door windows will open from the keyfob, a relay would be counter productive.

You can add a relay if that is how you want to handle it. There is a lot of room up in the overhead console where the map lights and sunroof switches are. 4 phillips head screws and unplug a wire harness and the console is out of the way. For a little more work, you can run a wire from the fuse panel, up the A pillar to the overhead and eliminate the relay.

BigDennis

Great information! I am adding a mirror mount for my Uniden R3 next week and your input helped me greatly!
Thank you,

timothyau

i need help where do measure wire which one. this is on is 500 2023. thank you