P2665

Code

Generic P — Powertrain

Fuel Shutoff Valve B Control Circuit/Open

Brand: Generic

Type: P — Powertrain

Views: UK: 22 EN: 44 RU: 27

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Page language: EN

Causes

Open or broken wiring in FSV B circuit
Corroded/loose connector or terminals at the valve or ECM
Faulty Fuel Shutoff Valve B (open coil or internal failure)
Blown fuse, faulty relay, or loss of power/ground to the circuit
Short or high resistance between valve and ECM (intermittent connection)
ECM driver output fault or internal ECM failure

Symptoms

Malfunction Indicator Lamp (MIL) / Check Engine light illuminated
Engine cranks but may not start or hard starting
Engine stalls or shuts down unexpectedly
Reduced/absent fuel pressure or fuel supply to injectors
No change after attempted key cycling or remote shutoff

What to check

Retrieve freeze frame and related codes; note key-on and engine state
Visual inspection of wiring and connectors at FSV B and ECM for damage, corrosion, or water intrusion
Check relevant fuses and relays for the fuel shutoff circuit
Backprobe the valve connector to verify voltage/ground while commanding the valve
Measure valve coil resistance with connector disconnected and compare to spec
Wiggle test harness while monitoring signal to reproduce intermittent faults

Signal parameters

Control type: low-side switch (ECM grounds) or high-side depending on vehicle — verify service manual
Expected coil resistance: typically single-digit to tens of ohms (example 5–40 Ω) — use OEM spec
Key ON (engine off) supply: ~12 V present to valve supply pin (if valve is supply-side powered)
Commanded state: ECM should switch control pin between ~0 V (grounded) and open/high; confirm with scope/voltmeter
Open-circuit condition: infinite/very high resistance or no continuity between valve and ECM

Diagnostic algorithm

Read and record all stored codes and freeze-frame data. Clear codes and attempt to reproduce.
Visually inspect connectors, pins, and harness for damage, corrosion, or signs of arcing at FSV B and along the harness to the ECM.
With ignition OFF, disconnect the FSV B connector and measure valve coil resistance across the valve terminals. Compare to OEM specification. An open (OL) reading indicates a failed valve.
With connector disconnected, check continuity between the valve connector and the ECM control pin. Repair any open wiring.
With backprobe and ignition ON, verify that the valve supply (if present) has battery voltage and that the ECM control line changes state (ground or switched voltage) when commanded (use scan tool to command if possible).
If no command is present but wiring is good, check fuses and relays feeding the circuit. Replace faulty components.
If wiring and supply are OK and ECM does not command correctly, use a scope to examine the control waveform for short/high-side failures or abnormal drive characteristics.
As a bench test, apply appropriate voltage to the valve coil briefly to confirm valve operation (observe safe shop practices and vehicle-specific procedure). Do not run valve continuously without proper current limiting.
Repair or replace damaged wiring/connectors or replace the fuel shutoff valve if confirmed faulty. If ECM output is suspected after verifying wiring and valve, consult OEM for ECM testing/replacement procedures.
Clear codes and road-test to verify repair. Re-scan for pending codes.