Use a multimeter to verify 12V Constant vs. 12V Switched.
In the PZ071, steering wheel signals are usually found on a 20-pin or 28-pin plug: toyota pz071 wiring diagram extra quality
If your PZ071 has a locked video-in-motion feature, you may need a bypass harness for the parking brake wire. Troubleshooting Common Issues Likely Cause No Power Blown "DOME" or "RADIO" fuse Replace 7.5A or 15A fuse in engine bay Settings Reset Constant 12V and ACC wires swapped Swap Yellow and Red wires Poor Radio Reception Antenna power (blue wire) not connected Connect "Ant Auto" to ACC No Sound Factory amplifier not turning on Jump the Remote/Amp Turn-on lead Use a multimeter to verify 12V Constant vs
For "extra quality" installations involving steering wheel controls (SWC) or backup cameras, you must identify the secondary harnesses. Steering Wheel Controls (SWC) Troubleshooting Common Issues Likely Cause No Power Blown
Often Pin 21 or 22 (depending on the specific sub-model). SW2 (Signal 2): Adjacent to SW1. SWG (Ground): Common ground for the steering resistors. Reverse Camera Trigger If you are adding a camera to a PZ071 screen: Reverse Signal: Look for a thin purple or red/white wire.
This connector handles the audio output for the back of the vehicle. Rear Left Speaker (+) Pin 2 (White): Rear Right Speaker (+) Pin 3 (Black): Rear Left Speaker (-) Pin 6 (Blue): Rear Right Speaker (-) Advanced Connectivity: 20-Pin & 28-Pin Diagrams