Voltage test of automobile accelerator

Pull down the throttle, there are six lines on the throttle, and two thick lines are motor control lines. One of these two wires has a voltage of about 1.9, which is the live wire of the motor, and the other one has no voltage and is the ground wire of the motor.

Measure the throttle position sensor ground wire.

The throttle position sensor consists of four wires, one of which is the ground wire. You can use a multimeter to measure the voltage of other wires to judge whether the grounding is good or not, and you can also use the battery voltage to judge the grounding situation.

Measure the throttle power supply.

One of the four wires of the throttle position sensor is the sensor power supply, but the voltage is only 5V. 5V voltage can be obtained by measuring with multimeter and ground or ground wire.

Measuring signal line.

According to the circuit diagram, there are two sensors in the throttle, which send out two signals respectively. When measuring, you will find that one of them also has 5V voltage, that is, after unplugging the sensor plug, two 5V voltages are measured. In actual maintenance, we can distinguish which signal has voltage and the other signal has no voltage.

Measure the sensor voltage without unplugging the sensor plug.

The voltage of the two sensors can be measured without dialing the sensor, and the sum of them is about 5V. If it is not within this range, there is something wrong with the line or throttle, and the voltage of 5V can still be measured without dialing the throttle. This is the power cord of the sensor.

Use diagnostic instrument and circuit diagram to help measure.

When repairing the car, we can ask the car diagnostic instrument to help us. The following figure shows the read throttle data flow, and technicians analyze the fault through the data on the diagnostic instrument.