What is the signal of pressure sensor downstream of Mercedes-Benz c200 throttle?

The voltage is unstable. There will be some problems when Mercedes-Benz c200 comes into the market, and the pressure sensor signal downstream of the throttle valve will be unstable. The mechanic's computer found that the signal voltage of the pressure sensor downstream of the throttle valve is unstable, high or low, or 0, and the fault code p0 17222 is too strong, so it needs to be replaced in time.