Powertrain
generic / SAE
P27B3
Internal Control Module Transmission Gear Select Performance
The internal gear-select interpretation logic in the transmission control module does not match external sensor inputs.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number7 / B3
Possible causes
- Internal logic drift after firmware update medium
- External gear-select sensor drift medium
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 200–1500 €
- Estimated time: 1–4 h
- Component: tcm
- MIL / check engine light
Sources
References
sae:J2012