P2435 moderate

Secondary Air Injection System Pump Malfunction Circuit Low

The P2435 code means the vehicle's onboard diagnostic system has detected: Secondary Air Injection System Pump Malfunction Circuit Low. This is a moderate severity code.

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Keep driving?: Short distances only
DIY difficulty: moderate
Estimated cost: $150 - $700 (parts and labor)

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Common Symptoms

Check Engine Light on
Failed emissions test
No air pump noise on cold start
Slightly rough cold start idle
Sulfur smell on cold start

Probable Causes (Ranked by Likelihood)

Short to ground in air pump circuit Very High
Corroded air pump relay or connector High
Damaged wiring to air pump motor Moderate
ECM air pump driver circuit fault Low

Step-by-Step Diagnostic Procedure

Test secondary air pump by applying direct power
Check air pump relay operation
Inspect wiring to air pump for damage
Verify ECM command to air pump relay with scan tool

Frequently Asked Questions

What does P2435 mean?

P2435 indicates: Secondary Air Injection System Pump Malfunction Circuit Low. The ECM detected an issue that needs diagnosis and repair.

Is P2435 urgent?

This code should be addressed soon to maintain proper engine operation.

What should I check first?

Start with a visual inspection of the sensor wiring and connector. Use a scan tool to read live data. For DPF codes, check soot loading level. For EVAP codes, check the gas cap first.