P2624 - Fuel Injector Control Pressure Regulator Circuit Low
System
Powertrain (Engine & Gearbox)
Technical Description
The control module has detected a fault in the Fuel Injector Control Pressure Regulator Circuit Low (P2624). The signal is below the lower threshold, typically from a short to ground or an internally shorted sensor.
Multimeter Test Points & Nominal Values
| Test Point / Component | Measurement | Nominal Target Range | Test Condition |
|---|---|---|---|
| Fuel Injector Control Pressure Regulator Circuit Low – Coil Resistance | Resistance (Ω) | 11.5 - 15.5 Ω (port) / 0.5 - 3.0 Ω (direct injection) | Connector disconnected at 20°C |
| Fuel Injector Control Pressure Regulator Circuit Low – Injection Pulse at operating cycle | Signal (ms) | 2.5 - 4.5 ms idle / 1.5 - 20 ms under load | Engine running |
| Fuel Injector Control Pressure Regulator Circuit Low – Supply Voltage | Voltage (V) | 11.8 - 14.4 V (port) / up to 65 - 90 V boost (direct) | Ignition ON / engine running |
Connector disconnected at 20°C
Engine running
Ignition ON / engine running
Oscilloscope Waveform Analysis
1 ms/div, 20 V/divPossible Causes
Short to ground on the signal wire or an internal short circuit within Fuel Injector Control Pressure Regulator Circuit Low
Chafed or pinched wiring harness along the signal path to Fuel Injector Control Pressure Regulator Circuit Low
Internal mechanical wear or carbon deposits inside Fuel Injector Control Pressure Regulator Circuit Low
Defective internal output driver or reference circuit in the control module for Fuel Injector Control Pressure Regulator Circuit Low
Symptoms
4
Recommended Solution
Measure signal wire resistance to chassis ground with connector unplugged (must exceed 10 kΩ; low reading confirms short to ground).
Verify loaded supply voltage and harness terminal pins at Fuel Injector Control Pressure Regulator Circuit Low.
Check circuit continuity and ground-side voltage drop (< 0.05 V) for Fuel Injector Control Pressure Regulator Circuit Low.
Perform fuel rail pressure-drop / balance test to identify leaking, stuck, or clogged injectors.
Mechanic's Tip
Pair a current clamp with your voltage channel on the scope. The distinct dip in the current ramp marks the physical pintle lift — no dip means the coil is energized but the needle is mechanically seized.