The constant power wire for the radio in a 1990 Ford Thunderbird should be green/yellow. The ground wire for this vehicle's stereo system should be black/light green.
You likely do not have the "Constant Power" wire connected at the back of your radio deck, it is often yellow in color.
Check your wiring harness to the radio. There are usually 2 "hot" wires, one red, or switched, and one yellow, or constant power. Check for loose connections there, or look for a loose ground wire, the black one. If that's all good, then could be an internal problem.
speaker is black-, blue with brownish stripe + on power connector their are 4 wires ,2 of them are black,1 green,last is black with green stripe
because you have the constant power and the ignition power crossed
power is red ground is black
constant power - orange power when key turned on - yellow
red
If you check the radio it should say the red wire is for "switched" power and the yellow wire is for constant power the car is turning off the power to the memory of the radio you need to find a constant power for the yellow wire..
go to www.modifiedlife.com.it has izuzu radio schematics for most years and models of isuzus.
blue and yellow
Don't know the color of the wire but you will just have to use a test light to see what wire is hot to the radio.
Somebody please answer this i am also having a problem. if i wire the aftermarket radio it does not even power on. but if i put the stock radio back in it works. could this be a problem with the ground? Help!