P0192 Code: Fuel Rail Pressure Sensor Circuit Low Input
The P0192 code means the signal from the fuel rail pressure (FRP) sensor is below its minimum value. It is almost always caused by a short to ground or by a missing 5 V reference.
- Severity
- High
- Can I keep driving?
- Yes, but with caution
- Estimated cost
- $80 to $700
- Difficulty
- Medium
- System
- Fuel Injection
- Applies to
- All OBD2 vehicles
On this page
What the P0192 code means
The fuel rail pressure (FRP) sensor A is threaded into one end of the fuel rail that feeds the injectors. The computer uses it to confirm that the pump and the regulator reach the pressure it asked for, which makes it essential on gasoline direct injection and common rail diesel engines.
The sensor sends a signal of roughly 0.5 to 4.5 V. A reading below the minimum means the signal is shorted to ground or the 5 V supply is missing: a shorted signal wire, an open 5 V reference or a damaged sensor. While the fault lasts, the computer believes pressure is missing. It increases the pump delivery, and you may see a long crank time, a lack of power and limp mode.
Keep in mind that the P0192 code points to the circuit where the computer saw the problem, not necessarily the part that failed. Check the wiring before you replace the sensor. The diagnosis steps below walk you through the tests one by one.
P0192 code symptoms
- Check engine light on steadily.
- Long crank time, or the engine does not start.
- Loss of power and limp mode.
- Jerking under load.
- Possible companion codes from the same sensor (low, high or intermittent signal).
Likely causes of the P0192 code
- Signal wire shorted to ground by rubbing against the engine or the chassis. Very common where the harness runs near metal brackets.
- Open or shorted 5 V reference, often shared with other sensors. If several sensors set codes at the same time, suspect it and look for a short on the common reference.
- Internal short in the sensor, which pulls the signal to ground.
- Connector with water or corrosion that creates a path between pins.
How to diagnose the P0192 code step by step
- Read the sensor in live data and compare it with what you expect: with the engine off the reading should be close to zero (or to residual pressure) and it should follow the commanded pressure closely when running.
- Inspect the connector. Unplug it, look for green, backed-out or oily pins, and push it back on firmly.
- Check the supply. There should be 4.8 to 5.1 V on the reference with the key on.
- Check the ground. The voltage drop between the sensor ground and the battery negative should be less than 0.1 V.
- Measure the signal with the connector plugged in using back-probe tips. It should change smoothly with the condition (position or pressure).
- Do a wiggle test. With the engine running, move the harness and the connector while you watch live data. A jump gives away the point of the fault.
- Check the continuity of each wire between the sensor connector and the computer connector with the key off.
How to fix the P0192 code
- Find where the wire rubs against ground and repair the insulation.
- If the code changes to a high signal when you unplug the sensor, the sensor is shorted: replace it.
- Dry and clean the connector if it had water in it.
- Use an original-quality or equivalent sensor: cheap generic sensors often have different response curves.
- Clear the codes, drive a full cycle and check in live data that the reading makes sense.
Technical reference data
- 5 V supply, ground and signal.
- Engine off: about 0.5 V.
- Approximate idle pressure: 40 to 70 bar (about 580 to 1,015 psi) on gasoline direct injection; 250 to 400 bar (about 3,600 to 5,800 psi) on common rail diesel.
- The signal rises in proportion up to about 4.5 V at maximum pressure.
- Approximate values: check the manufacturer data for your engine.
Brand-specific notes
The sensor is not always sold separately, so check how it is built on your engine before you order parts. That matters if you are chasing the P0192 code and the wiring tests out fine.
P0192 on Ford
On many diesels the sensor comes built into the rail and is not sold separately.
P0192 on Nissan
On many diesels the sensor comes built into the rail and is not sold separately.
P0192 on Hyundai
On many diesels the sensor comes built into the rail and is not sold separately. On gasoline direct injection (GDI) engines it is usually replaceable.
P0192 on Kia
On many diesels the sensor comes built into the rail and is not sold separately.
P0192 on Volkswagen
On gasoline direct injection engines (TSI) the sensor is usually replaceable.
P0192 on GM
On gasoline direct injection engines the sensor is usually replaceable.
Questions about the P0192 code
There are no questions about this code yet. Tell us about your case: vehicle, symptoms and what you have already checked.