After I install the aftermarket head unit my dimmer stop working and dash stop working. Y it that happen? Please help.

 

Please refrain from using profanity in your thread title.

You likely popped a fuse, or left your dimmer switch unplugged

 

Sorry lol I really didn't think it was that bad at all. But negative on all your suggestion. Everything seem ok but when I took the power cable from the headunit and connect it together with the black n red strip cable ( interior lighting wire) the dash come on but when I turn on the headlights the dash lights go off.

 

you miswired something

 

There are 2 black/red stripe wires in the radio connectors. One is for the dash lights, the other for a speaker. What is the signal name of the radio wire you connected to the black/red stripe wire. Are you splicing wires directly to the nissan wire harness or do you have an adapter such as a Metra kit?

 

Its my fault. Because I was inpatient to install my headunit I decided not to wait to buy the harness for the radio and cut the factory harness and just tap in all the lines. It dorked but it was a mess. That's when everything started to go wrong, I found the factory plug at a junkyard , so I repair it back. But still having the no dash light problem

 

I bought a adapter at walmart. I did see the wire and I tap it in Ruth power wire and the dash comes on but when I turn on the headlights it turns off.

 

My car came with Bose factory system.

 

If its not a fuse/loose wire then it sounds to me like you fried your TCU (time control unit)

not hard to replace its under the panel below the steering wheel

 

Replace it yesterday. Tcu

 

Where is fuse #40?

 

fuse box to the left of the driver's knee...iirc it's a 7.5A (red) but don't quote me.

 

Is it for 4th only . Because I don't see it

 

4th gen maxima

 

what are you using exactly to connect/splice the wires?

worse case disconnect your mess that you created and see if the lights go back on.

 

That is smart thinking. I'll start all over by disconnecting all wires. And fix the dash lights, then I'll start to connect wires one by one.

 

Was battery hooked up while all this? If so something touched something else and shorted it out. Check wiring for the hu and fuses.

 

Ok thanks I just bought a multimeter to fine the short. And I do remember tapping two wires together and there was a spark. Smh

 

one of the factory stereo wires controls the dimming on the factory stereo,maybe you goofed it somehow?i think its red with an orange or yellow stripe