Automatic Transmission/Transaxle Flashcards

A vehicle shifts harshly into all gears and has no torque converter clutch (TCC) apply. Which sensor failure is the MOST likely cause?

Answer: Throttle position sensor (TPS)

A faulty TPS gives the controller incorrect load data, producing harsh shifts and preventing proper TCC apply.

Aerated, foamy automatic transmission fluid on the dipstick most commonly indicates which condition?

Answer: Overfilled fluid level

An overfilled level lets the rotating components whip air into the fluid, creating foam.

Which component allows the front wheels of a transaxle-equipped vehicle to rotate at different speeds while turning?

Answer: Differential

The differential, integrated into the transaxle, lets the drive wheels turn at different speeds during cornering.

A torque converter that is locked up (TCC stuck applied) will cause which symptom?

Answer: Engine stall when coming to a stop

A stuck-applied TCC mechanically links the engine to the transmission, stalling the engine as the vehicle stops.

In a Simpson planetary gear set, what provides the reduction needed for first gear?

Answer: Holding the rear carrier while the sun gear drives

In low gear the input drives the sun gear and the rear carrier is held, producing maximum gear reduction.

A technician finds metallic particles clinging to the transmission pan magnet. What does this primarily indicate?

Answer: Gear or bearing wear

The magnet attracts ferrous metal, so accumulation points to wearing gears, bearings, or hard parts.

Which check should be performed FIRST when diagnosing a slipping automatic transmission?

Answer: Check fluid level and condition

Fluid level and condition are the quickest, most common causes of slipping and must be verified first.