P042B — Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 2

What Does P042B Mean?

P042B is a diagnostic trouble code indicating: Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 2. This code relates to the emission controls system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P042B

⚠️ Check Engine Light (MIL) illuminated
⚠️ Catalyst Temperature Sensor not operating within expected parameters
⚠️ Reduced efficiency or performance of related system
⚠️ Failed emissions test

Common Causes

🔍 Catalyst Temperature Sensor degraded or contaminated
🔍 Mechanical wear or binding in Catalyst Temperature Sensor
🔍 Incorrect Catalyst Temperature Sensor installed (wrong part number)
🔍 Related system mechanical issue affecting Catalyst Temperature Sensor readings

Frequently Asked Questions

What does P042B mean?

P042B indicates: Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 2. The vehicle's computer has detected that the Catalyst Temperature Sensor is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P042B?

Yes, P042B is generally safe to drive with in the short term. However, it should still be addressed to pass emissions testing and prevent potential secondary issues.

How much does it cost to fix P042B?

Repair costs for P042B typically range from $50 to $250, 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 and clean Catalyst Temperature Sensor
🔧 Replace degraded Catalyst Temperature Sensor
🔧 Check for related mechanical issues affecting readings

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.

P042B: Catalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 2