P24E0

Code

Generic P — Powertrain

Reductant Purge Control Valve B Stuck Closed

Brand: Generic

Type: P — Powertrain

Views: UK: 22 EN: 26 RU: 29

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Page language: EN

Causes

Defective purge control valve (stuck mechanically or electrically)
Clogged/restricted reductant line, filter, or valve port (crystallized DEF deposits)
Open or short in valve wiring or poor connector contacts (corrosion, bent pins)
Failed valve driver in the powertrain control module (PCM/ECM)
Low system supply voltage or blown fuse
Faulty reductant pump or pressure issue upstream

Symptoms

Malfunction Indicator Lamp (MIL) / check engine light
Reduced or no reductant dosing to SCR system; elevated NOx emissions
Failed emissions test or NOx-related diagnostic limits exceeded
Possible reduced engine power or limp mode on some vehicles
Diagnostic trouble code(s) stored for reductant dosing circuit

What to check

Read stored codes and freeze-frame data with a capable scan tool; note freeze data and PID values for reductant system
Perform an active test / command of Purge Valve B from the scan tool and observe response (flow, audible click)
Visually inspect valve, wiring harness, and connector for corrosion, damage, or fluid ingress
Measure connector supply voltage with key ON (referenced to vehicle ground) and check control signal when commanded
Check coil resistance of the valve with connector disconnected
Check continuity and resistance of harness between valve connector and ECM pin

Signal parameters

Supply voltage at valve: typically near battery voltage (approx. 11–14 V with key ON)
Control method: switched ground or PWM from ECM; commanded duty cycle 0–100% depending on vehicle
Typical solenoid coil resistance (generic): approximately 5–50 Ω (wide variation by manufacturer) — consult vehicle spec
Expected current when energized: roughly 0.1–2 A depending on valve design
When commanded open in an active test, valve should click and allow flow; no click + correct voltage suggests mechanical bind or clog

Diagnostic algorithm

Verify the code and related codes. Record freeze frame and live data for reductant system PIDs.
Use the scan tool to command Purge Valve B ON/OFF while listening/feeling for an audible click or change in pressure/flow. Note response.
Inspect valve connector for corrosion, bent pins, water ingress or DEF crystallization. Clean and reconnect, then re-test.
With harness disconnected, measure valve coil resistance at the valve terminals. Compare to service specification or to the general expected range. If open/shorted, replace valve.
Backprobe valve connector with key ON and command ON to verify supply voltage and switching/ground signal from ECM. If no supply or command, check fuses, relays and wiring continuity to ECM.
Check continuity between the valve connector and ECM pin(s). Repair any open or high-resistance sections and check for shorts to ground or battery.
If electrical checks are OK but valve does not operate, remove valve and bench-test with controlled 12 V power (observe correct polarity and duty characteristics). Inspect internals for deposits or mechanical seizure.
Inspect reductant lines, filters and any solenoid-mounted strainers for blockages or crystallized DEF. Clean or replace as needed.
If valve and wiring test good but control signal is unexpected or absent, inspect ECM driver output and related ECU grounds and power. Consider ECM replacement only after all other causes are eliminated.
After repair, clear codes and perform active tests and a road/drive cycle to confirm proper operation and that the code does not return.