P077C — Output Shaft Speed Sensor Circuit Low

What Does P077C Mean?

P077C is a diagnostic trouble code indicating: Output Shaft Speed Sensor Circuit Low. This code relates to the transmission system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P077C

⚠️ Check Engine Light (MIL) illuminated
⚠️ Output Shaft Speed Sensor reading at zero or minimum value
⚠️ Related system not functioning or in fail-safe mode
⚠️ Harsh or delayed shifting

Common Causes

🔍 Open or broken wire in Output Shaft Speed Sensor circuit
🔍 Poor ground connection at Output Shaft Speed Sensor
🔍 Faulty Output Shaft Speed Sensor with no output signal
🔍 Disconnected or loose Output Shaft Speed Sensor connector
🔍 Blown fuse in related circuit

Frequently Asked Questions

What does P077C mean?

P077C indicates: Output Shaft Speed Sensor Circuit Low. The vehicle's computer has detected that the Output Shaft Speed Sensor is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P077C?

Only short distances if absolutely necessary. P077C affects a critical system and should be diagnosed within a few days to avoid further damage.

How much does it cost to fix P077C?

Repair costs for P077C typically range from $20 to $500, 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 Output Shaft Speed Sensor circuit
🔧 Clean and secure Output Shaft Speed Sensor connector and ground points
🔧 Replace failed Output Shaft Speed Sensor

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.

P077C: Output Shaft Speed Sensor Circuit Low