Powertrain
Definition only
Lights the check engine lamp
P2643: Torque Management Feedback Signal B Low
Standardized SAE J2012 code · P26xx — Computer and output circuits
What does P2643 mean?
The torque feedback signal B reads below its valid range. Source sends a value below physical possibility or the bus signal is stuck low.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Source module sends invalid low value
- Medium Signal stuck low on the bus
Likelihood is a general estimate across vehicles; your make and model may differ.
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P2643 in the community
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