P2285 — Injector Control Pressure Sensor Circuit Low — 6.0 Power Stroke

Diagnostic reference for P2285 on 6.0L Power Stroke (2003.5–2007) HEUI injection.

Updated October 15, 2026

What it means

Generic definition: injection control pressure (ICP) sensor signal voltage is below its valid range. On the 6.0L Power Stroke this is the HEUI oil-pressure sensor, not a fuel-rail sensor. A low ICP sensor signal is usually an open or shorted sensor, oil-soaked connector, or harness fault rather than an actual pressure problem; check the 5 V reference and signal at the ICP sensor.¹

Most likely causes

1. ICP sensor internal failure or signal short to ground — Sensor element or internal circuitry fails low, or the signal wire is shorted to ground causing PCM to see voltage below valid range.¹²
2. Oil intrusion into ICP sensor connector / harness — Engine oil wicks into the ICP connector and contaminates terminals, leading to low or erratic sensor voltage. Oil contamination of the ICP sensor connector is a known failure on 6.0L.¹²³
3. Open or high-resistance in ICP 5 V reference or signal circuit — Chafed, corroded, or disconnected wiring between PCM and ICP sensor drops reference or signal voltage, producing a low circuit reading.¹
4. PCM reference voltage supply issue affecting ICP circuit — A fault in the PCM 5 V reference supply can pull the ICP signal low; verify reference voltage at the sensor with key on.¹

How to diagnose

1. Verify code and freeze frame; confirm P2285 is present and note engine state at set.
2. Inspect ICP sensor connector for oil intrusion, damaged pins, corrosion, and harness chafing; look for oil in the connector body.
3. Key-on, engine-off: check ICP sensor 5 V reference and ground at the sensor connector; compare to spec and to other 5 V sensors.
4. Backprobe ICP signal wire at the sensor and at the PCM harness; measure signal voltage key-on/engine-off and during cranking; look for short to ground or open.
5. Swap ICP sensor with a known-good unit (if available) and re-evaluate signal voltage to isolate sensor internal failure.
6. Check related ICP codes and data: P2284/P2286 for sensor range/performance, P2290/P2291 for actual low pressure; differentiate circuit fault from true pressure loss.
7. Inspect high-pressure oil system integrity only as context: if actual ICP pressure is low, consider high-pressure oil leaks (STC fitting, branch tubes/standpipes/dummy plugs, HPOP) and IPR operation, but circuit low is primarily electrical.

Specs and test values

Common mistake to avoid

Replacing the ICP sensor or HPOP when the real problem is a high-pressure oil leak. If ICP stays low while the IPR is commanded hard during cranking, look for leaks at the STC fitting, standpipes, dummy plugs and injector seals before buying parts. Source: Bulletproof Diesel — 6.0L high-pressure oil system diagnostic.

Parts and tools you may need

• Digital multimeter
• Backprobe pins / breakout box
• Known-good ICP sensor for substitution test
• Dielectric grease
• Shop manual wiring diagram for 6.0L Power Stroke

Tools you’ll need

• digital multimeter — Measures 5 V reference, ground, and ICP signal voltage at the sensor and PCM to detect shorts, opens, or out-of-range signals.
• OBD-II scan tool — Reads P2285, freeze frame, and live ICP voltage/pressure data to confirm circuit fault versus actual pressure loss.
• backprobe kit — Allows safe access to ICP sensor signal, reference, and ground pins without damaging connector seals.
• inspection light — Reveals oil intrusion, corrosion, and pin damage inside the ICP connector and harness.

Rough cost and difficulty

Typical US independent-shop figures; labor runs about $120–$180 per hour (dealers charge more). Confirm the diagnosis before buying parts.

When to see a pro

If diagnosis points to PCM reference voltage faults, internal harness damage, or you need to differentiate a true high-pressure oil leak from a sensor circuit fault, have a qualified diesel technician perform pinpoint electrical tests and pressure verification. Do not perform step-by-step repair of safety-critical high-pressure oil systems. If the vehicle stalls or shows sudden loss of power, stop driving and seek immediate professional inspection.

Check for recalls

Recalls are tied to your truck’s VIN, so check yours directly: enter the VIN at NHTSA’s recall lookup. Open safety recalls are repaired free at a dealer.

Sources