Here is my verified edited version of Toyota's wiring color code for the stereo in the AE86/AE85. It may also apply to all Toyota models prior to 1987. You will find 2 male plugs for your stereo, one larger (blue?) and a one smaller (black?). No power antenna was equipped in the USDM AE86, so positions 4 & 8 (refer to diagram) are not used. You will also notice that the rear speakers will share the same colors as the front speakers. Only difference being that the rear speakers are on the smaller plug, while the front speakers on the larger plug. To determine which is rear and which is front without tracing the wire through the whole loom, you will find that all wires going to the rear speakers will be 22AWG. The remaining wires will be 18AWG.
WIRING HARNESS DIAGRAM :
Toyota AE86 stereo wiring harness
POWER & ACCESSORIES :
wire
color
ID
polarity
12v constant/memory
white/red
D
+ positive
12v switch/power
blue/black
3
+ positive
ground
white/black
7
- negative
illumination
green
9
+ positive
dimmer
???
???
???
TRG/power antenna
none
none
none
SPEAKERS :
wire
color
ID
polarity
driver front +
black/grey
2
+ positive
driver front -
white
6
- negative
passenger front +
red
1
+ positive
passenger front -
black/red
5
- negative
driver rear +
black/grey
B
+ positive
driver rear -
white
E
- negative
passenger rear +
red
A
+ positive
passenger rear -
black/red
C
- negative
*** if any descreptancies between your knowledge or other sources and what is shown here, please leave an email with the subject, the difference, and where you found the other source ***