P07A3
Transmission Friction Element A Stuck On
Friction element A does not release when commanded — the apply piston cannot retract, leaving the clutch or band engaged. The transmission cannot complete shifts that need element A released, leading to harsh engagement or stall when stopping.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
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
Common causes
Ordered by how often each turns out to be the cause.
- Stuck apply piston (cannot retract)Common
- Broken or weak return springPossible
- Carbon or debris buildup preventing free movementLess likely
Parts involved
- Clutch Pack A
- Apply Piston
- Return Spring
P07A3 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.