What this code means

The TCM detected excessively harsh downshifts. The transition between gears during deceleration is abrupt.

Symptoms

• Check Engine Light
• Harsh downshifts
• Vehicle lurches on deceleration
• Engine braking feels excessive
• Driveline shudder on downshift
• Abrupt speed change during coast-down

Common causes

• Faulty shift timing solenoid
• Torque converter clutch not releasing
• Pressure control solenoid malfunction
• Valve body wear
• Incorrect TCM calibration

Diagnostic steps

1. Monitor shift quality PIDs during deceleration
2. Check TCC release timing
3. Test pressure control solenoid
4. Inspect shift solenoid operation
5. Review TCM software version

Repair notes

Replace pressure control solenoid or valve body. TCM reflash may be available from manufacturer.

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