Trans not shifting as commanded.
P0780 — also written PO78O, P 0780, 0780 — is the OBD-II code for shift malfunction. Same code, same fix: this page covers every spelling of it.
P0780 is the gearbox's way of saying it tried to swap cogs but the timing was all wrong. We see this constantly on high-mileage Volvo V70s and older Freelander 2s where the 'sealed for life' oil has turned to liquid coal.
P0780 is a transmission fault code, typically costing £300–£3000 to put right in a UK garage.
What P0780 actually feels like to drive
- The car 'hunts' between 2nd and 3rd gear, acting like it can't make up its mind.
- A violent 'thump' when slowing down for a roundabout, usually the 3-2 downshift.
- Engine revs flare up like you've pushed the clutch in during a gear change.
- Transmission goes into 'Limp Mode', locking you in 3rd gear to get you home.
- The 'Gearbox Service Required' message appears only once the oil is hot after a motorway run.
What causes P0780?
- Solenoid fault
- Valve body
- Internal wear
UK vehicles that throw P0780 most often
- Volvo V70/XC70 2.4D (Aisin TF-80SC) 2007-2015
- Land Rover Freelander 2 2.2 TD4 2006-2014
- Vauxhall Insignia 2.0 CDTi (AF40-6) 2008-2017
- Ford Mondeo Mk4 2.0 TDCi (Aisin Auto) 2007-2014
- Volkswagen Golf Mk5 1.9 TDI (09G 6-speed Auto) 2004-2009
- BMW 3 Series E90 (GM 6L45 box) 2006-2011
How P0780 is fixed
- Diagnostic scan
- Valve body service
- Rebuild if severe
The P0780 misdiagnosis that wastes money
I’ve lost count of how many owners come in having already chucked a brand new battery or a set of speed sensors at the car because some 'expert' on a forum told them it was a voltage drop issue. While a weak battery messes with modern autos, P0780 is usually the mechanical reality of the gearbox not being able to complete a physical shift. Nine times out of ten on the Aisin boxes found in Volvos and Vauxhalls, it’s a sticky solenoid in the valve body or 'sludge' in the fluid, not an electrical ghost in the machine.
What a UK garage should charge for P0780
For a basic diagnostic and fluid refresh, you're looking at £180 to £250. If we have to pull the valve body and fit a refurbished solenoid kit (like Rostra or TransGo), expect a bill between £600 and £900 including labour and fresh ATF. If the internal clutches are burnt out and it needs a full rebuild from a specialist like Stephens Engineering, you won't get much change out of £2,500 to £3,200. Main dealers will usually just refuse to repair and quote £5k for a new unit.
P0780 repair cost in the UK
Most P0780 repairs land between £300–£3000 including parts and labour. The spread is wide because the cheap fix (a sensor, a hose, a leak) and the expensive fix (a major component) throw the same code — which is why a proper diagnosis before parts are bought saves the most money.
Bob's tip on P0780
If a garage immediately quotes you £2,500 for a 'recon box' without even dropping the pan, walk away. Ask them to perform a 'stall test' and check the adaptions on their diagnostic kit (Snap-On or Autel). Insist on a 'drain and fill' with the correct spec fluid first—something like Motul or Castrol Transmax—rather than a full power flush, which can sometimes dislodge more grit and make a tired box worse. If the fluid smells like burnt toast and looks like Marmite, you're likely looking at a rebuild, but always try the software update and fluid change first.
Can you drive with P0780?
Drive gently to garage.
Urgency: high.