Torque Management Feedback Signal A High
The P2640 code means the vehicle's onboard diagnostic system has detected: Torque Management Feedback Signal A High. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $100 - $800 (parts and labor)
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What Are the Symptoms of P2640?
- Harsh bumpy shifts
- Unnecessary engine torque reduction
- Sluggish acceleration response
- Transmission shifts feel abrupt
What Causes P2640? (Most Likely First)
- ECM overreporting torque output Very High
- Short to voltage in torque signal circuit High
- Incorrect ECM calibration after service Moderate
- Aftermarket tune affecting torque values Low
Can I Still Drive with P2640?
Short distances only. P2640 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
Why are my shifts so harsh with P2640?
The TCM thinks the engine is producing more torque than it actually is, so it applies excessive clutch pressure and aggressive torque reduction during shifts.
Can an aftermarket tune cause P2640?
Yes. Performance tunes that modify torque reporting can cause the TCM to receive incorrectly high values, disrupting shift quality.
Will P2640 cause transmission wear?
Harsh shifting puts extra stress on transmission clutch packs and bands, potentially accelerating wear and reducing transmission lifespan.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P2640?
-
Compare reported torque to dynamometer or calculated values
-
Check torque signal circuit for short to power
-
Verify ECM calibration matches vehicle specifications
-
Remove aftermarket tunes and retest
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Which Vehicles Commonly Get P2640?
- 2010-2020 Toyota Tundra
- 2012-2019 Honda Odyssey
- 2008-2018 Ford F-150
- 2011-2020 Chevrolet Silverado
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