P07B9 — Transmission Park Position Sensor/Switch B Circuit Low

What Does P07B9 Mean?

P07B9 is a diagnostic trouble code indicating: Transmission Park Position Sensor/Switch B 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 P07B9

⚠️ Check Engine Light (MIL) illuminated
⚠️ Transmission Park Position Sensor/Switch B 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 Transmission Park Position Sensor/Switch B circuit
🔍 Poor ground connection at Transmission Park Position Sensor/Switch B
🔍 Faulty Transmission Park Position Sensor/Switch B with no output signal
🔍 Disconnected or loose Transmission Park Position Sensor/Switch B connector
🔍 Blown fuse in related circuit

Frequently Asked Questions

What does P07B9 mean?

P07B9 indicates: Transmission Park Position Sensor/Switch B Circuit Low. The vehicle's computer has detected that the Transmission Park Position Sensor/Switch B is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P07B9?

Only short distances if absolutely necessary. P07B9 affects a critical system and should be diagnosed within a few days to avoid further damage.

How much does it cost to fix P07B9?

Repair costs for P07B9 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 Transmission Park Position Sensor/Switch B circuit
🔧 Clean and secure Transmission Park Position Sensor/Switch B connector and ground points
🔧 Replace failed Transmission Park Position Sensor/Switch B

1
Find your vehicle above
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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.

P07B9: Transmission Park Position Sensor/Switch B Circuit Low