P2446

Code

Generic P — Powertrain

AIR System Pump Stuck On Bank 2

Brand: Generic

Type: P — Powertrain

Views: UK: 25 EN: 45 RU: 24

AI status

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ready

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Page language: EN

Causes

Stuck or welded relay or stuck high-side/low-side driver keeping pump powered
Control valve or bypass stuck in the open position allowing pump to run
Short to battery in pump power feed or control wiring
PCM or pump control module fault (failed driver)
Failed air pump motor that is mechanically stuck in run condition or has internal short
Corroded/poor ground or damaged connector causing erratic operation

Symptoms

MIL (Check Engine) illuminated and P2446 stored
AIR pump noise running continuously or audible at times it should be off
Reduced fuel economy and possible unusual exhaust behavior
Blown fuse related to the AIR pump circuit (if short draws excessive current)
Possible premature catalyst heating/damage if pump runs at inappropriate times

What to check

Scan for codes and freeze-frame data; confirm P2446 and any related codes (P0410, P0411, etc.)
Use a scan tool to monitor and command the AIR pump ON/OFF (verify PCM commands)
Visually inspect fuses, pump relay, wiring harness, and connectors for damage or corrosion
Listen for pump operation and note when it runs relative to engine state and scan tool commands
Measure voltage and ground at the AIR pump connector with pump commanded OFF and ON
Check continuity/shorts between pump power circuit and battery, and between control circuit and PCM

Signal parameters

Battery voltage at pump power feed: ~11–14 V when engine is on (may be fused constant or switched)
Control/driver signal: either switched ground or switched +12V depending on vehicle — should change state when PCM commands OFF/ON
Pump current draw (typical range): approx 0.5–5 A (varies by vehicle) — unusually high draw indicates mechanical binding or short
When commanded OFF by PCM: power to pump or driver should be removed (voltage on control circuit should reflect OFF state)
When commanded ON by PCM at cold start: pump should be energized for the specified time interval and then turn OFF

Diagnostic algorithm

Retrieve all stored and pending codes and freeze-frame data. Note engine temperature and conditions when the code set.
Using a bidirectional scan tool, command the AIR pump OFF/ON. Observe whether the pump follows the commands and whether PCM reports successful commands.
With the ignition ON (engine off), measure voltage at the pump power terminal and at the control terminal while commanding OFF/ON. Identify whether the power feed or control driver is providing power when it should not.
Inspect and test the AIR pump relay and related fuses. Swap relay with a known-good identical relay if available to check behavior.
Disconnect the pump connector and command OFF/ON. If the pump still runs when disconnected, suspect relay or hard-wired short to battery. If pump does not run when disconnected, bench-test the pump separately for internal faults or unexpected behavior.
Check wiring harness for shorts to battery, corrosion, damaged insulation, or poor ground. Repair any damaged wiring and connectors.
Inspect AIR control valves, check valves, and bypass components on Bank 2 for mechanical sticking or carbon buildup; clean or replace as required.
If wiring, pump, and valve operation test good, evaluate PCM/pump control module output. Replace PCM only after confirming other faults have been ruled out and following manufacturer procedures.
After repairs, clear codes and perform a road/cold-start test to confirm the pump is operating only during intended conditions and that P2446 does not return.

Likely causes

Stuck relay or relay contacts welded closed supplying constant power to pump
Short in power feed (fused hot) or stuck high-side driver feeding pump continuously
Faulty pump control solenoid/valve or stuck bypass that forces pump operation
Open/shorted wiring or poor connector/ground at pump or relay
Failed PCM output driver (less common)

Fault status

⚠️ Status

P2446 — AIR System Pump Stuck On (Bank 2): PCM detects the secondary air injection pump or its control circuit is energized when it should be off on bank 2.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.5 hours