P0C99 — Hybrid/EV Battery Temperature Sensor L Circuit Low

What Does P0C99 Mean?

P0C99 is a diagnostic trouble code indicating: Hybrid/EV Battery Temperature Sensor L Circuit Low. This code relates to the vehicle systems system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P0C99

⚠️ Check Engine Light (MIL) illuminated
⚠️ Hybrid/EV Battery Temperature Sensor L reading at zero or minimum value
⚠️ Related system not functioning or in fail-safe mode
⚠️ System warning light illuminated

Common Causes

🔍 Open or broken wire in Hybrid/EV Battery Temperature Sensor L circuit
🔍 Poor ground connection at Hybrid/EV Battery Temperature Sensor L
🔍 Faulty Hybrid/EV Battery Temperature Sensor L with no output signal
🔍 Disconnected or loose Hybrid/EV Battery Temperature Sensor L connector
🔍 Blown fuse in related circuit

Frequently Asked Questions

What does P0C99 mean?

P0C99 indicates: Hybrid/EV Battery Temperature Sensor L Circuit Low. The vehicle's computer has detected that the Hybrid/EV Battery Temperature Sensor L is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P0C99?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P0C99 for extended periods may cause additional problems.

How much does it cost to fix P0C99?

Repair costs for P0C99 typically range from $20 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

🔧 Repair broken wire or restore ground in Hybrid/EV Battery Temperature Sensor L circuit
🔧 Clean and secure Hybrid/EV Battery Temperature Sensor L connector and ground points
🔧 Replace failed Hybrid/EV Battery Temperature Sensor L

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.

P0C99: Hybrid/EV Battery Temperature Sensor L Circuit Low