Accelerator pedal sensor low.
P2122 — also written P2122, P 2122, 2122 — is the OBD-II code for pedal position sensor 'd' low. Same code, same fix: this page covers every spelling of it.
Your throttle pedal has two sensors for safety, and 'D' has just flatlined. It's a classic Vauxhall and Nissan gremlin that'll leave you stranded in limp mode on the A9.
P2122 is a sensors fault code, typically costing £150–£500 to put right in a UK garage.
What P2122 actually feels like to drive
- Car goes into 'Limp Mode' and won't rev past 2,000 RPM.
- Engine Warning Light (MIL) and 'Service Vehicle Soon' message on the dash.
- Dead throttle pedal – you floor it and absolutely nothing happens.
- The car 'stutters' or jerks suddenly while you're cruising at 60mph.
- Throttle response feels 'lazy' or inconsistent, like it’s thinking about moving.
What causes P2122?
- Failed pedal sensor
- Wiring
UK vehicles that throw P2122 most often
- Vauxhall Corsa D/E 1.2 & 1.4 (2006-2019)
- Nissan Qashqai 1.5 dCi (J10/J11) 2007-2017
- Ford Focus Mk3 1.6 TDCi (2011-2015)
- Volkswagen Golf Mk6/Mk7 (All engines) 2009-2017
- Vauxhall Astra J/K (A14NET/B16DTH engines) 2010-2020
- Renault Clio 1.2 16v (2005-2014)
How P2122 is fixed
- Pedal sensor replacement
The P2122 misdiagnosis that wastes money
I see lads at other shops jumping straight to a new ECU every time this code pops up on an Astra, and it's a massive waste of the customer's brass. Nine times out of ten, the sensor or the wiring harness near the bulkhead is the culprit. I've also seen people throw cheap £30 eBay pedals at it, only for the car to go back into limp mode two weeks later because the signal voltage is all over the shop. Check the connector pins for green crusty corrosion before you buy a single part.
What a UK garage should charge for P2122
A local indie like mine will charge you £60 to £90 for the initial diagnostic. A Bosch or Hella pedal assembly usually runs between £120 and £220 depending on the car. Labour is a doddle—usually an hour (£60–£80)—so you’re looking at £250 to £350 all-in. If you go to a main dealer, expect that to climb north of £500 once they add their 'premium' labour rates and 100% markup on the plastic pedal assembly.
P2122 repair cost in the UK
Most P2122 repairs land between £150–£500 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 P2122
If your garage tells you 'it needs a whole new computer,' tell them to hold their horses. Insist they do a 'pin-to-pin continuity test' between the pedal and the ECU. It’s a 20-minute job with a multimeter. Also, ask them if they're using a genuine OEM part or a quality brand like Hella or Bosch. If they fit a 'white box' special from a budget factor, you’ll be back in the workshop before your next MOT. Genuine pedals for VAG or Ford cars aren't actually that dear compared to the labour of doing the job twice.
Can you drive with P2122?
Limp mode possible.
Urgency: high.