I know lot of members of your SC forum did navtool installations. I am having problem to install with my RX 300 nav for backup camera. I installed the navtool by following configs:

1. 12v dc power red wire connected with dvd ecm plug N3 pin# 18 (grey)
2.Black ground wire connected with trunk metal body.
4. Blue wire connected with plug N3 # 14 pin (red and black) with reverse light switch.
5.White wire connected with the same ground metal body.
6.Navtool RGB out connected with N4 plug by the male and female harness comes with navtool.

7. I connected rear view camera Boyo VTL402C power red wire to N3 #14 and black ground wire with same ground body metal also.

Now when I turn the engine on i saw the red light on in Navtool device that mean it has power. But the nav screen got black. Only INFO, DISPLAY,AUDIO button works. The map or other screen got black. If I reverse the gear R the screen stay black, nothing changed.
So I remove the navtool and wires and put original configaration. The gps nav screen come back normal. What is wrong in this case? Any ideas?
I attached few pics.

 

Did you try the other video port on the NAVtool? Other than that sound like a short in one of your taps.

 

yes I tried both ports and same result. Should I use different ground connections instead of four together.

 

I had a similar problem after installing my NavTool. After turning on the key, I got the Lexus logo screen and then it went black. Got suggestion from this forum to try hitting the Map button to turn on the display. Worked like a charm. Hope it works for you.

 

I tried according to your suggestion but same result. I also use Nav ecm N3 pin # 17 (ground black and white) wire as ground but no luck. I checked the boyo backup camera using N3 pin # 14 (reverse wire red and black) with different monitor (audio box 7" screen) if it works. When ever I shift the gear to R it displayed the rear view with audio box monitor. But when ever I attached the Navtool with nav screen it totaly black. No change if I hit map or destination button. Only if I hit display, Info or Audio button it shows their result only. But If I remove the Navtool from the nav ecm it becomes normal. The red light in the navtool lighted when I connected. May be the navtool is bad.

 

I'm looking at the manufacturer website, more specifically their installation instructions NAVTOOL install PDF It looks like you need to verify your wiring schematic. And if that doesn't resolve it, sounds like it's time for their tech support: http://www.navtool.com/techsupport.aspx

 

Thanks for your help. I will contact with Navtool tech support.

 

Thanks again. The Navtool RGB was bad and sent to their tech department but no help. They told me better option will be buy new one but they don't have in stock and they don't know when it will be available. Navtool has very bad customer service. I bought a used one from a forum member and works very good. Here is the link for a video: http://www.youtube.com/watch?v=TObZ0...ature=youtu.be