temperamental radio (HU) and dome light...:/

so i have an 08 2wd base model. i bought it from the dealer May of this year (2011). only AFTER i finish all the paperwork and leave the dealership do i notice that the HU wasnt turning on. figured a connection was bad or was a blown fuse. so i pulled the HU from the dash...perfectly fine. checked fuses...perfectly fine. by this time it was dark and i noticed the dome light wasnt on either. i gave up and decided to go back to the dealer after work the next day.

get up the next morning. jump in my truck and low and behold, the dome light comes on when i open the door. turn the key, and radio comes on! so i think everythings all good until i get in after work, and once again, radio and dome light are not cooperating.

now, toyota said that it was common in the 08 and to purchase a stock radio thru them and it would be fine. well, i had planned on an aftermarket HU anyway, they said that would correct the problem also. so i finally purchase an aftermarket one and install it. (yes, i installed it correctly...not my first HU install)

well, it still hasnt corrected the problem and toyota seems to want to blame me since i installed the aftermarket one myself, even though they have records of me bringing the truck in for the exact same problem with the stock HU!!

so in conclusion, the radio and dome light turn on when they want to and dont work when they dont want to. any help/suggestions/troubleshooting tips would be greatly appreciated!

 

I had the same issue when I bought my truck. Although it also affected the keyless entry and air bag. It ended up being a bad wire in the junction box. The previous owner put the battery in backwards was what the mechanic said. Anyway cost me $300.00.

 

$300?! damn...

sooo, junction box...under the steering wheel?
why would the batt being installed backwards cause that to happen tho?

and you wouldnt happen to know which wire would you? hahahahah!! just figure i'd ask.

 

I do not. The Junction box is behind the battery. I do not have an electrical aptitude. I tried fuses and relays. He stated it was the radio wire/auxiliary, but I do not know which one. He told me he has seen it before where the battery being hooked up wrong changes polarity and messes with electrical stuff. After a year of it cutting off and on whenever it felt like it, I really didn't care. $300 bucks was worth having it work for my entire 2 hour commute.

 

My HU likes to shut off randomly when i run the AC full blast. Its always been daytime when it happened so i dont know if it affected the dome light at all but i replaced the fuse and it seemed to fix it for a while? Although a fuse would fail completely if it were to fail right? No intermittent working? Its been doing it again recently ill have to check the fuse.

Subbed to figure out how to fix this....super annoying...

 

yeah, its been three months and it bugs the sh*t outta me. hahaha! but thanks for the info. i'll have to look into this. might be the culprit.

yeah, if a fuse were to blow, it wouldnt be intermittent like mine is. but what year and style truck doyou have? thats wierd that it shuts off when the AC is full blast...have u had a mechanic check it out yet?

but if and (hopefully) when i figure this out, i'll be sure to update this thread!

 

month-later-bump. haha. still no solution!

 

polarity bein the direction of current flow.if it was changed should have run positive charge to ground.should have blown fuses

 

What!

You aren't an electrician are you?

There is more than likely a loose connection somewhere.