P023F

Code

Generic P — Powertrain

Fuel Pump Secondary Circuit/Open

Brand: Generic

Type: P — Powertrain

Views: UK: 22 EN: 85 RU: 31

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Page language: EN

Causes

Open or high-resistance wiring in the fuel pump secondary circuit
Corroded, loose or damaged connector at the fuel pump or relay
Faulty fuel pump relay or relay socket
Blown fuse or fusible link in the pump feed
Failed fuel pump motor
Poor or corroded ground for the pump circuit

Symptoms

Engine cranks but will not start or hard to start
No fuel pump prime or no audible pump run on key ON
Low or no fuel pressure at the rail
Intermittent stalling or loss of power if the pump drops out
Check Engine Light / MIL illuminated with P023F stored

What to check

Confirm DTC P023F and view freeze-frame / related codes
Verify battery voltage is healthy (12 V+ under load) before testing
Listen for fuel pump prime with key ON; attempt scan-tool pump command
Inspect fuses, fusible links and fuel pump relay and swap with known-good relay if available
Visually inspect pump wiring and connectors for corrosion, heat damage or rodent chew
Backprobe pump connector to measure voltage at pump positive with key ON and while cranking

Signal parameters

Expected supply voltage at pump connector with key ON/engine cranking: approx. battery voltage (~11–14 V) if relay and wiring intact
Open-circuit symptom: near 0 V at pump positive when pump should be energized
Typical pump current draw (nominal): a few amps to ~10 A when running (varies by pump design) — a very low or zero current indicates open circuit; excessive current suggests internal motor short
Ground continuity: near 0 Ω between pump ground and chassis ground (low resistance)
Pump motor winding resistance (typical): low single-digit ohms for many in-tank pumps — check OEM spec

Diagnostic algorithm

Record DTC(s) and freeze-frame data. Note vehicle state when code set (key ON, cranking, running).
Visually inspect accessible pump wiring, connectors, relay, fuse and ground. Look for corrosion, damage, loose pins or water intrusion.
Verify battery voltage is sufficient. Low system voltage can cause false faults.
Check fuse and fusible links for continuity; replace if blown and retest.
Swap or bench-test the fuel pump relay (if external) or check relay socket for corrosion/loose terminals.
Use a scan tool or jumper to command the pump. While commanding, backprobe the pump power terminal and measure voltage. If no voltage, trace back to relay/PCM.
With pump command active, measure voltage while cranking and measure current draw to detect open circuit or high resistance. Take care—use appropriate ammeter clamp or inline meter rated for the expected current.
If no voltage at pump but relay is being commanded, check continuity between relay output and pump connector; repair any open circuits.
Check ground continuity from pump housing/ground wire to chassis/engine ground. Clean and repair any poor ground connections.
If wiring and connectors are good but pump shows open winding (infinite resistance) or no current draw, replace the fuel pump.
If pump and wiring test good but the driver is not providing output, verify PCM/ECM control signals and inspect for related driver codes. Consider PCM replacement only after wiring and pump are verified faulty-free.
After repairs, clear codes, perform functional test and road test to confirm the issue is resolved and code does not return.

Likely causes

Broken or disconnected power/ground conductor to the pump (harness damage, connector issue)
Blown fuse or failed relay preventing pump feed
Failed fuel pump motor (open winding)
Faulty pump driver inside the PCM/ECM or a disconnected control module