P28BF — Cylinder 12 Ion Current Sense Circuit High

What Does P28BF Mean?

P28BF is a diagnostic trouble code indicating: Cylinder 12 Ion Current Sense Circuit High. This code relates to the powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P28BF

⚠️ Check Engine Light (MIL) illuminated
⚠️ Cylinder 12 Ion Current Sense reading stuck at maximum value
⚠️ Related system operating erratically or in default mode
⚠️ Reduced engine performance

Common Causes

🔍 Short to voltage in Cylinder 12 Ion Current Sense wiring harness
🔍 Corroded or water-damaged Cylinder 12 Ion Current Sense connector
🔍 Faulty Cylinder 12 Ion Current Sense outputting maximum voltage
🔍 Damaged wiring rubbing against metal components
🔍 ECM/PCM internal fault (rare)

Frequently Asked Questions

What does P28BF mean?

P28BF indicates: Cylinder 12 Ion Current Sense Circuit High. The vehicle's computer has detected that the Cylinder 12 Ion Current Sense is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P28BF?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P28BF for extended periods may cause additional problems.

How much does it cost to fix P28BF?

Repair costs for P28BF 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

🔧 Inspect and repair Cylinder 12 Ion Current Sense wiring for short to voltage
🔧 Clean or replace corroded Cylinder 12 Ion Current Sense connector
🔧 Replace faulty Cylinder 12 Ion Current Sense

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.

P28BF: Cylinder 12 Ion Current Sense Circuit High