P27B1 — Internal Control Module Transmission Range Select Performance

What Does P27B1 Mean?

P27B1 is a diagnostic trouble code indicating: Internal Control Module Transmission Range Select Performance. This code relates to the powertrain system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P27B1

⚠️ Check Engine Light (MIL) illuminated
⚠️ Internal Control Module Transmission Range Select not meeting expected output
⚠️ Degraded performance of related system
⚠️ Reduced engine performance

Common Causes

🔍 Internal Control Module Transmission Range Select degraded from age or contamination
🔍 Mechanical wear in Internal Control Module Transmission Range Select or related parts
🔍 Restriction or blockage affecting Internal Control Module Transmission Range Select
🔍 Calibration drift in Internal Control Module Transmission Range Select

Frequently Asked Questions

What does P27B1 mean?

P27B1 indicates: Internal Control Module Transmission Range Select Performance. The vehicle's computer has detected that the Internal Control Module Transmission Range Select is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P27B1?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P27B1 for extended periods may cause additional problems.

How much does it cost to fix P27B1?

Repair costs for P27B1 typically range from $50 to $400, 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 Internal Control Module Transmission Range Select for contamination or wear
🔧 Replace Internal Control Module Transmission Range Select
🔧 Address any related mechanical faults

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.

P27B1: Internal Control Module Transmission Range Select Performance