Downstream O2 sensor heater fault on bank 1.
P0036 — also written POO36, P 0036, 0036 — is the OBD-II code for ho2s heater control circuit (bank 1 sensor 2). Same code, same fix: this page covers every spelling of it.
O2 sensor heater control circuit (Bank 1, Sensor 2 — downstream). Same family as P0030 but downstream. Almost always a failed heater element in the sensor.
P0036 is a sensors fault code, typically costing £80–£300 to put right in a UK garage.
What P0036 actually feels like to drive
- Engine warning light within a mile of cold start
- No drivability issues
- Slight MPG drop
- Possible MOT emissions warning
- Code persists after clearing within one drive cycle
What causes P0036?
- Failed downstream O2 sensor
- Wiring or fuse fault
UK vehicles that throw P0036 most often
- Vauxhall Corsa / Astra petrol
- Ford Fiesta / Focus 1.0 / 1.6
- VW Polo / Golf 1.4 TSI
- Renault Clio / Megane
- Toyota Auris / Yaris
How P0036 is fixed
- Replace sensor
- Inspect wiring
The P0036 misdiagnosis that wastes money
Check the heater fuse first — same as P0030. If the fuse is intact and the sensor's resistance is out of spec, it's a genuine sensor failure.
What a UK garage should charge for P0036
Downstream O2 sensor £65–£160 fitted, fuse check £15–£30, wiring repair £45–£90.
P0036 repair cost in the UK
Most P0036 repairs land between £80–£300 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 P0036
Buy the OEM-spec sensor from a known brand (Bosch, NTK, Denso) — cheap eBay sensors fail within months. The £20 saving costs £100+ in re-replacement.
Can you drive with P0036?
Drivable.
Urgency: low.