The computer shows that the Bora throttle position sensor is faulty. How to detect whether the harness voltage of the throttle plug is normal?

Wiring of throttle plug: marked with numbers: 1 and 2 are idle motor 12V power supply and ground wire, 3 is idle switch signal wire, 4 is throttle power supply 5V, 5 and 8 are throttle signal wires, 7 is throttle ground wire, multimeter is set at 20V DC voltage, and probes are connected to 4 and battery negative electrode respectively, which will display nearly 5V voltage. When the probe is connected to 4 and 5 or 8 above, the throttle will be displayed.