P0729
Système
Powertrain (Transmission)
Scanner requis
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Gear 6 Incorrect Ratio

Understand P0729, common causes, and the right FOXWELL scanner to diagnose it.

Sixth gear ratio does not match calculated value on 6+ speed automatics.

Symptômes courants

  • No 6th gear
  • High RPM at highway speed
  • Poor fuel economy

Causes typiques

  • Worn 6th clutch pack
  • Low ATF level
  • Failed solenoid controlling 6th gear
  • Valve body wear

Quel scanner choisir ?

Full-system scanner (engine, ABS, SRS, transmission, service resets)

Utilisez les données en direct et le freeze frame avant de remplacer des pièces. Les codes ABS, SRS et U nécessitent souvent un scanner mult systèmes.

Conseils de diagnostic

  • Enregistrez le freeze frame lors de la première apparition du code
  • Effacez le code uniquement après avoir corrigé la cause
  • Vérifiez les codes en attente associés
  • Vérifiez que la batterie est au-dessus de 12,4 V avant de suspecter un capteur

Scanners FOXWELL recommandés

Questions fréquentes

Can I diagnose P0729 with a basic code reader?
P0729 may set in the engine module, but related diagnostics often benefit from an enhanced or full-system scanner with live data and freeze frame.
Is it safe to drive with P0729?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.