I have tried for a few days now and I don't usually ever have trouble installing audio gear...

However I still cant get my H/U to turn on...
I have tested there is power on the 12v constant and thats all ok
I have used the stock ground wire, aswell as multple chassis grounding points and no luck...

Does anyone else have a suggestion for me?

Car is an Aw11 MR2, below is the wiring colours and i have checked this many times.

right rear+ ---- red,
right rear- ---- white,
left rear+---- black,
left rear- ---- yellow,
front right+ ---- cyan,
front right- ---- blue,
front left+ ----pink,
front left- ---- purple,
earth ---- brown,
antenna ---- black/red stripe,
permenant +12v ----grey,
ign +12v ---- blue/yellow,
sub control ---- pink/blue

A question i have... If the ING wire isn't working, will have effect the headunit turning on?
I can't find my multimeter to check if there is power going from it, any other way of checking?
I have replaced the fuse twice now and that doesnt seem to be the problem...

The headunit is a Sony XAVA1, It was pulled out of my N13 Nissan Exa and it was still working...

Thanks in advance

check the fuse using a test light to make sure its not blown if thats ok take the red and yellow wire and give them a constant 12V (ie straight to bat pos) take the negative and have it connected to the negative, if it works then either one of these in your install isn't working properly.

So if i connect the HU straight to the battery, it wont damage it at all?
I might give that a go...
The fuse is fine...

Okay... testes the headunit and that all fine...
Must be somethign wrong with the wiring in the car...
Will have to look into it tomorrow as i have to goto work now...

Thanks for your help 20Hurtz

No worries use a test light for your constant 12 and you acc/ign 12v if both these light up with the test light then its your ground thats a prob, i do'nt recomend using the factory ground find a point that is bare metal and conects directly to the chasis try and keep the wire under 40cm use 15 amp wire.

Toyota wiring

Grey is Acc
Blue/Y is Constant
if there is a wire in the plug directly below the b/y that is the illumination wire and its normally green

Thanks guys!
Ill test the constant and ING this morning.

HLUCIN8 thanks for the wiring colouring, I did find out yesterday afternoon that this was was the case i changed the wiring around and still didnt work... Unfortunately the plug has been cut off already so i'll have a search for a green wires, thanks!

Dont stress if you dont find the green wire (excluding the spkr one of cause) not all toyota looms have an illumination wire.

If you have used a test light and have power on the ign and const wires with your test light earthed through the earth wire in the loom ( not on the body) then theres nothing wrong with the wiring and id start looking at the deck. check the fuse it the deck, it may be blown. Otherwise it may be an internal fault with the deck.