Reset WIRE COLOUR CODE

Pin 1 - Signal (Green/Yellow) Pin 2 - Signal Return (Grey/Red) Pin 3 - Signal (Orange/Red) Pin 4 - +5V Reference (Orange/Yellow) Pin 5 - Ground (Black) Pin 6 - Not Used

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1991 Ford F150 Truck Car Stereo Wiring Schematic

Visit the on-line store, know as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem.
Toyota Service Manuals

red wire is live (battery) yellow wire live only when ignition is on, black wire is earth(car body) there should also be 4 pairs of wires green,white,grey and purple these are your speaker wires you'l notice with the pairs of same colour eg white one is solid colour one has a black stripe the solid colour goes to live + on your speaker the one with stripe goes to - on speaker, same goes for the rest of the pairs hope this helps

wires are colour code for the purpose of being able to distinguish what wire is which at the end of the wiring loom(harness) If all the wires were the same colour then identifying where each terminal went would be impossible. IT means that if you have a main red wire with a purple stripe in the engine compartment then where ever you find that wire in the car /under dash / in the boot it is the same wire regardless of how many connections and diversions there are.

This should help.

Use a multimeter, and test each wire individually as you turn on/off lights. You won't need a colour code with this method.

work it out with a meter ,,,,find perm 12v feed neg and pos ---yes could be any coloured wire depending on car maker,after finding perm 12v feed for memory look for pos from ign switch,now speaker wires are easy as both will be same colour for a speaker but one will have a band through it if not sure or colour blind like yours truelly then use pos and neg on speaker wire till you hear a thump from speaker then you know you have the right wires and location of speaker ,,ie.. front left back right ect ....Now you are a fully experianced radio fitter ??

what is your email i will email you the diagram



Mark