Any chance on getting that diagram? Thanks!!The illumination circuit ground runs into the combination meter(gauge cluster). Poor engineering! If there is a short then a fuse should blow not your combination meter!
I had the same problem with my illumination lighting. I research the wiring diagrams from Toyota TIS and came up with a quick fix. I spliced into the illumination ground and ran a new ground point. Much cheaper then $850!!
Let me know if anyone is still having problems with the illuminations. I can foward you the wiring diagram and my quick fix.