P0190 - FUEL RAIL PRESSURE SENSOR “A” CIRCUIT
Description of DTC code P0190
The CCM (Component Comprehensive Monitor) monitors the sensor circuit to the PCM (Powertrain Control Module). In case the voltage is not within the calibrated levels, the test fails.
The Fuel Rail Pressure Sensor (FRP) measures the fuel pressure near the fuel injectors and sends a signal to the PCM (Powertrain Control Module) that uses this information to adjust the fuel injector in the pulse width and this way measure the fuel in each cylinder
The FRP (Fuel Rail Pressure) sensor varies its resistance taking into account changes in pressure, if the pressure drops, the electrical resistance decreases, and if the pressure rises, the resistance increases. Due to changes in the resistance the voltage drop at the sensor terminals is affected, therefore, it sends an electrical signal to the Power Train Control Module (PCM), which corresponds to the pressure. This sensor is considered passive, since it is connected to the circuit so that the variation of the resistance causes a variation in the total current flow.
Symptoms of fault code P0190
- Check Engine service light illuminates on the board.
- The engine may not start.
Causes of OBD2 P0190
The problems that may accompany a P0190 OBD2 code can be:
- The fuel level is very low.
- The fuel pump may be in poor condition.
- The FRP (Fuel Rail Pressure) sensor cables may be short-circuited.
- There is a bad electrical connection of the Fuel Rail Pressure Sensor (FRP).
- Possibly the FRP sensor (Fuel Rail Pressure) is defective.
Possible solutions of the DTC code P0190
To solve the DTC code P0190 you can do the following:
- Inspect the cables and connectors of the Fuel Rail Pressure Sensor (FRP) for any of these components to rub or wear. Similarly, check the terminals of these connectors to see if they are corroded or burned. Repair or change if necessary.
- Check the sensor and the circuits associated with it. In general, the FRP sensor has 3 cables. Disconnect the wire harness that leads to the FRP sensor and using a digital multimeter, verify that the 5 volt power circuit that goes to the sensor to verify that it is being turned on. The red wire is 5 volt power and the black wire is ground. If there is 12 volts in the sensor when there should be 5 volts, it is indicative of a short circuit in the wiring of the Power Train Control Module (PCM) to the sensor.
- Make sure there is good ground in the FRP (Fuel Rail Pressure) sensor. You could connect a test light to the positive connector of the battery and the other end to the ground of the FRP sensor circuit. If the test light does not turn on, it means there is a problem in the circuit. In the case of switching on, move the FRP sensor wiring harness to check that the test light does not blink, if it does, it is indicative that one of the cables is failing. Repair and change if necessary.
- You can replace the Fuel Rail Pressure Sensor (FRP).