Hello, I am looking to hardwire some devices and I found a power connecting the map/dome lights. Doing research the plug seems to be the J33 plug, does anybody have a diagram on which wires are hot with ign on and the ground wires?
Don't know if you're still looking for this info, but here it is for a 2014: 1 - GROUND 2 - MICROPHONE -> SNS2 3 - MICROPHONE -> MCO- 4 - MICROPHONE -> MCO+ 5 - MICROPHONE -> MACC 6 - BLANK 7 - BLANK 8 - GEARSHIFT ILLUMINATION + 9 - SWITCH ILLUMINATION + 10 - BLANK 11 - DOOR SIGNAL FROM BODY ECU (ACTIVE LOW) 12 - DOOR -> REAR DOME LIGHT 13 - SAFETY CONNECT GREEN LIGHT +12V 14 - SAFETY CONNECT RED LIGHT +12V 15 - SAFETY CONNECT SOS BUTTON + 16 - SAFETY CONNECT SOS BUTTON - 17 - ON -> REAR DOME LIGHT (GROUND) 18 - BLANK 19 - COMMON -> REAR DOME LIGHT (+12V) 20 - UNSWITCHED +12V
I wired my dashcam from that connector. But I do not remember the pins Just try to find the largest one for ign Ground I think its white
here's what it looks like without any of the extra features no ign, only constant 12v and gnd... no good for dash cam
In answering a question I posed to this forum in March 2025 I can now confirm that there is no unused wire harness pigtail in 2010's that are not shipped with the HomeLink mirror. And after following circuit board copper tracks under a microscope at my office I can confirm that there is no ignition switched +12V signal on the dome light's circuit board. However, for purposes of adding a Gen 2 HomeLink mirror to a 2010 I think the signal identified above as pin #8=Gearshift Illumination=White Map Light LED can be used to power the electronic dimming subsystem in the mirror. I think this line is +12V when the car is powered on AND the headlights are turned on, which roughly equals when the mirror's dimming system would need to be powered and active. I can't imagine that the dimming subsystem would require +12V when the headlights are off. This comment assumes that the mirror's unpowered state is unimpeded (not dimmed) mirror viewing, something I'm unsure of.
Toyota never wires for uninstalled options available in higher trims. However I simply wired my dimming Homelink to constant 12v and Gnd years ago with no problems. Even factory Homelink systems still open gates and garage doors with switched 12v off. The dimming function has a 6 ma draw but my car is still under 30ma when shutdown. If you have a dealer retrofit a Homelink mirror they will give you a battery powered unit with no external wiring.
For those of you attempting to attach a Prius Gen 2 HomeLink dimming rear view mirror to a Gen 3 Prius, the missing +IGN signal to drive the dimming feature of the mirror can be obtained from connector pin #8 Gear Shift Illumination +. This is the green wire in the connector shown in the above color photograph from poster "anonymous". On my bare bones 2010 Prius the shifter knob is not illuminated. Instead there is a single white LED that shines on the gear shift from the overhead console. Some people refer to this white LED as a map light, but its light output is too low to serve that purpose. The green wire in the console's 20-pin connector goes to +12VDC whenever the headlights are turned on. This signal powers the white LED in my 2010. When the car is turned off and the headlights time out, the green wire returns to 0VDC. The current sourcing capacity of the green wire is sufficient to supply 100mADC to the dimming subsystem in an auto-dimming mirror. BTW, when you harvest a dimming mirror from a junked Gen 2 Prius, get the wire harness, too. And take as much of the wire feeding the harness' connector as you can because the 20-pin connector is at least 18" from the mirror.
