P0780 and related codes: shift errors, shift timing and slipping

What does P0780 mean?

Each change in an automatic gearbox has an expected time and an expected result: the engine speed should fall by a set amount in a set time as the next clutch takes over. When a change takes too long, ends too quickly, lets the engine speed flare, or leaves two clutches applied at once, the computer stores one of these codes. They describe a result rather than a cause: the reason is usually low or worn fluid, a sticking valve or solenoid, or worn clutches.

What causes P0780?

1. Low or worn-out fluid, which slows every clutch as it applies
2. A sticking shift or pressure solenoid, or a worn valve body
3. Worn clutch packs or friction elements
4. A shift timing solenoid or its circuit at fault
5. Adaptation values that no longer match a worn gearbox

What to check first for P0780

• Check the fluid level and condition before anything else
• Note which change is named and how it feels: a flare, a thump or a delay
• Read the other transmission codes, which often show the cause behind the result
• Ask whether a fluid change or an adaptation reset is the maker's first step for this code

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