Code result
P27B1
Internal Control Module Transmission Range Select Performance
High severity
What it means
This code indicates internal control module transmission range select performance. It relates to the cylinder contribution / balance and may affect performance, emissions, or drivability depending on the exact failure.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Faulty sensor or actuator
mediumThe component monitored by this code may be worn, failed, or reading out of range.
Wiring or connector issue
mediumCorroded, damaged, or loose connections can cause circuit or signal faults.
Related component failure
mediumA problem in an upstream system can cause this code to set.
Related help
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