P1151 — Lack Of HO2S21 Switch - Sensor Indicates Lean

What Does P1151 Mean?

P1151 is a diagnostic trouble code indicating: Lack Of HO2S21 Switch - Sensor Indicates Lean. This code relates to the manufacturer-specific powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P1151

⚠️ Check Engine Light (MIL) illuminated
⚠️ Lack Of HO2S21 Switch - Sensor Indicates Lean not functioning as expected
⚠️ Related system may be in fail-safe mode
⚠️ Reduced engine performance

Common Causes

🔍 Faulty Lack Of HO2S21 Switch - Sensor Indicates Lean
🔍 Wiring or connector issue in Lack Of HO2S21 Switch - Sensor Indicates Lean circuit
🔍 Related mechanical or electrical fault
🔍 ECM/PCM issue (rare)

Frequently Asked Questions

What does P1151 mean?

P1151 indicates: Lack Of HO2S21 Switch - Sensor Indicates Lean. The vehicle's computer has detected that the Lack Of HO2S21 Switch - Sensor Indicates Lean is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P1151?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P1151 for extended periods may cause additional problems.

How much does it cost to fix P1151?

Repair costs for P1151 typically range from $80 to $300, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect Lack Of HO2S21 Switch - Sensor Indicates Lean and related wiring
🔧 Replace faulty Lack Of HO2S21 Switch - Sensor Indicates Lean

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P1151: Lack Of HO2S21 Switch - Sensor Indicates Lean