This unit uses a non-standard wiring harness. If your unit came without the original pigtail connector, the manual’s wiring diagram is mandatory . Guessing the pinout can fry the internal preamp section instantly.
However, decades later, the original has become a rare gem. Lost to garage cleanouts, tossed with old glovebox contents, or deteriorated into illegibility, the manual is essential for properly wiring, tuning, and troubleshooting this vintage unit. pioneer eeq 45wx4 instruction manual