P025A

Code

Generic P — Powertrain

Fuel Pump Module A Control Circuit/Open

Brand: Generic

Type: P — Powertrain

Views: UK: 29 EN: 247 RU: 48

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Blown fuse or defective fuel pump relay
Open, chafed or disconnected wiring in pump control circuit
Corroded or poorly connected pump module connector or ground
Faulty fuel pump module (internal controller or motor)
PCM/BCM driver transistor or software fault
Intermittent connection due to vibration or damaged harness

Symptoms

MIL (check engine light) with P025A stored
Engine cranks but will not start or hard starting
Intermittent or complete loss of engine power
Low or no fuel rail pressure
No audible fuel pump prime on key‑ON
Fuel pump runs only intermittently or ceases while driving

What to check

Read and record DTCs and freeze frame data with scan tool
Verify battery voltage is healthy (12V+ at key ON and cranking)
Listen for fuel pump prime during key‑ON (audible hum)
Inspect fuses and fuel pump relay and replace if suspect
Visually inspect wiring and connectors at the fuel pump module for corrosion, heat damage, or disconnection
Backprobe pump module connector while commanding pump ON and measure voltage and ground

Signal parameters

Key‑ON (prime) supply: battery voltage present at pump power feed (≈12 V) before cranking
Command signal from PCM: PWM or switched supply — expected change when PCM commands pump ON (0–12 V variable depending on design)
Module ground continuity: near 0 Ω to chassis (
Pump resistance (typical range): low ohms (vehicle‑specific; often
Pump running current (typical): a few amps up to 20 A depending on pump — elevated draw indicates load or short; zero current indicates open circuit
Fuel rail pressure: should rise to expected operating/prime pressure when pump is commanded (compare to vehicle spec)

Diagnostic algorithm

Retrieve PIDs/freeze frame and all stored codes. Note conditions when fault set.
Confirm battery voltage ≥12.0 V; poor battery can cause false faults.
With key‑ON (engine off), listen for pump prime. If no prime: check pump fuse and relay for power and swap relay with known good if available.
Backprobe fuel pump module power and ground while commanding pump ON with a scan tool. Verify battery voltage at power feed and solid ground. If no voltage to module, trace upstream (fuse/relay/wiring).
If voltage present but pump not running, measure current draw to detect open circuit or internal module failure. Zero current with proper supply indicates open or failed module.
Inspect connector pins for corrosion, bent pins, or poor contact. Repair/clean and retest.
Check continuity of control wiring to PCM and check PCM output with scan tool/oscilloscope for expected switching/PWM when commanded. If PCM output is absent and wiring is good, suspect PCM/driver fault.
Wiggle test harness while monitoring to find intermittent opens. Repair damaged wiring and secure harness away from heat or moving parts.
If wiring, fuses, relays, and grounds are good, replace the fuel pump module and retest. Relearn or program module if required by manufacturer.
Clear codes and road test to confirm repair. If code returns, escalate to module bench testing or PCM evaluation.

Likely causes

Open wiring or broken connector to the fuel pump module
Corroded/poor ground at module
Failed fuel pump module (internal control electronics)
Blown fuse or stuck/failed fuel pump relay
PCM output driver failure

Fault status

⚠️ Status

P025A — Fuel Pump Module A Control Circuit/Open. PCM detected open/fault in fuel pump module control circuit. Can cause no start, low fuel pressure, or intermittent stall.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5–3.0 hours