Glow plug control circuit fault.
P0380 — also written PO38O, P 0380, 0380 — is the OBD-II code for glow plug / heater circuit 'a' (diesel). Same code, same fix: this page covers every spelling of it.
Your glow plugs aren't getting the juice they need to pre-heat the cylinders, usually because one of the plugs has burnt out. It's a classic winter headache for UK commuters, especially on Vauxhall and Ford diesels.
P0380 is a electrical fault code, typically costing £80–£500 to put right in a UK garage.
What P0380 actually feels like to drive
- Engine starts 'lumpy' or on three cylinders for the first 10 seconds on frosty mornings.
- Excessive white/grey smoke from the exhaust immediately after a cold start.
- The 'Service Vehicle Soon' message on Vauxhalls (often without a management light).
- The glow plug coil light on the dash flashes or disappears suspiciously fast.
- Stop/Start system stops working because the ECU detects an emissions-related fault.
What causes P0380?
- Failed glow plug
- Glow plug relay/module fault
- Wiring
UK vehicles that throw P0380 most often
- Vauxhall Insignia 2.0 CDTi (A20DTH) 2008-2015
- Ford Focus 1.6 TDCi (DV6) 2004-2012
- Vauxhall Astra J 1.7 CDTi 2009-2014
- Volkswagen Golf Mk6/Mk7 2.0 TDI (CFGB/CRBC) 2009-2017
- Nissan Qashqai 1.5 dCi (K9K) 2007-2013
- Fiat 500 1.3 MultiJet 2007-2016
How P0380 is fixed
- Glow plug replacement
- Module replacement
The P0380 misdiagnosis that wastes money
I see folks constantly throwing £150+ at a brand-new glow plug control module because their cheap code reader says 'Circuit A Fault.' In my experience, nine times out of ten, it’s just one or two dead Bosch or Beru plugs that have gone open circuit. The module is usually fine; it's just crying for help because the resistance is out of spec. People also forget to check the heavy-duty midi-fuse in the engine bay fuse box—I've seen plenty of 'failed' modules that just had a blown 60-amp fuse caused by a temporary short.
What a UK garage should charge for P0380
A basic diagnostic to confirm the circuit fault usually runs you £50–£80 at an indie. For a set of four quality Bosch or Denso plugs, expect to pay £60–£100 for parts and another £70–£120 in labour. If it’s a Vauxhall with the 'pressure sensing' plugs, hold onto your hat—those are £120 EACH. A genuine control module can push the bill up by £150 plus VAT. If you go to a main dealer, you won't see much change from £500, especially if they try to upsell you a loom repair.
P0380 repair cost in the UK
Most P0380 repairs land between £80–£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 P0380
If you're taking your motor to a garage for this, ask them specifically if they've done a resistance test on each individual plug before they quote you for a new module. A proper tech will use a multimeter; anything over 1.5 ohms is a dud. Also, ask about their 'snap risk' policy. On the 1.3 CDTi engines, these plugs love to snap in the head. If they don't mention using penetrating oil or an induction heater, walk away. You want a garage that uses a vibrating torque wrench to back them out slowly, not a 'gung-ho' lad with a breaker bar.
Can you drive with P0380?
Drivable, hard cold starts.
Urgency: low.