P0782 Fault Code in Toyota: Causes, Symptoms, and Fixes

The Transmission Control Module (TCM) has detected that the 2nd-to-3rd gear shift did not happen properly. Similar to P0781 (1–2 shift malfunction), but this one is specific to the 2–3 shift sequence.

Symptoms:

1. Check Engine Light ON
2. Hard or delayed shift between 2nd and 3rd gear
3. Transmission may skip 3rd or get stuck in limp mode
4. Slipping or flaring (engine revs increase but speed doesn’t) during 2–3 shift
5. Harsh engagement on acceleration
6. Reduced fuel efficiency

Common Causes:

1. Faulty shift solenoid (often Solenoid B or C, depending on transmission design)
2. Low/contaminated transmission fluid
3. Valve body issues – sticking valves or blocked passages
4. Worn 3rd gear clutch pack or band
5. Hydraulic pressure problems (leaks, pump wear)
6. Wiring/connectors – damaged harness to solenoid
7. Faulty TCM/PCM (rare)

Diagnostic & Fix:

1. Check fluid – correct level, not burnt/dirty.
2. Inspect solenoids – test electrically and with scan tool commands.
3. Check wiring/connectors – especially at transmission harness.
4. Scan live data – compare commanded vs actual gear shifts.
5. Inspect valve body – clean or repair sticking valves.
6. Internal check – worn 3rd gear clutches/bands may require rebuild.