P24DE

Code

Generic P — Powertrain

Reductant Purge Control Valve B Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 22 EN: 35 RU: 20

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Page language: EN

Causes

Short to battery or ignition feed on the purge valve B control wire
Corroded, damaged or disconnected connector at the purge valve
Open or high-resistance wiring between valve and control module
Failed reductant purge control valve (internal short or stuck)
Blown or incorrect fuse / failed relay supplying the circuit
Poor ground or corroded ground point

Symptoms

MIL/Check Engine light illuminated
Reduced or disabled reductant purge function; possible DEF system warnings
No change when commanding purge valve ON/OFF from a scan tool
Possible limp-home mode or reduced emissions system performance
Eventual repeated codes if condition persists

What to check

Read freeze frame and pending codes; note conditions when code set
Visually inspect valve B connector and wiring for damage, corrosion, and proper seating
Scan tool: command purge valve B ON/OFF and observe live voltage/current
Measure control wire voltage at the valve with connector connected and while commanding
Measure resistance of the purge valve coil with connector disconnected (compare to spec)
Check for continuity to ground and for short to battery/ignition on the control wire

Signal parameters

Typical commanded voltage: 0 V (OFF) to ~12 V (ON) for direct drive solenoids; may be PWM-controlled
Typical coil resistance (disconnected): usually 10–50 ohms for solenoid valves (manufacturer-specific)
Expected PWM duty cycle when commanded: 0–100% depending on command and module strategy
Control signal frequency (if PWM): commonly 20–200 Hz (varies by system)
Fault is logged when measured voltage/current is above expected range or not matching commanded state

Diagnostic algorithm

Verify the code and capture freeze-frame data. Note engine state, battery voltage, and temperature when fault occurred.
Visually inspect valve B connector and harness for corrosion, pin damage, chafing, or water entry. Repair any damage.
With ignition ON, back-probe the valve control connector. Use a scan tool to command the valve ON and OFF while observing voltage and current. Record readings.
If voltage is higher than expected with command OFF or not following commands, disconnect connector and check for voltage present at the harness — verify if there is a short to battery/ignition.
Measure coil resistance of the valve with connector disconnected and compare to specification. Very high or infinite resistance = open coil; very low may indicate shorted coil.
Check continuity between the valve harness and ECU pin, and check continuity to ground. Look for high resistance or opens.
Repair wiring faults: replace damaged sections, clean/replace corroded connectors, repair grounds. Use dielectric grease on connectors after repair.
If wiring and connectors test good, substitute or bench-test the identical valve (if available) or replace valve B.
If problem persists after wiring and valve replacement, consider ECU output driver fault — verify with manufacturer procedures before replacing ECU.
Clear codes and perform a functional test and road/drive cycle to confirm repair.

Likely causes

Damaged insulation allowing short to battery/ignition circuit
Corrosion or bent terminals in the valve connector
Failed purge valve with internal electrical fault
Open or intermittent ground at valve or wiring harness
Connector pin pushed out or poor mating causing high resistance

Fault status

⚠️ Status

Reductant Purge Control Valve B Circuit High — control signal voltage higher than expected (possible short to battery, open/high-resistance wiring, connector or valve fault).

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours