Officially? A wall of jargon. To most people? Absolutely nothing. That's exactly why we built the app.
Plug into any code reader and you'll get the same line every other app shows you. Technically correct. Practically useless.
"Same family of fault as P0113, but on the engine coolant temperature sensor: the signal voltage is stuck high, which the ECU reads as an absurdly cold engine — minus 40 territory. That's electrics, not temperature: a dodgy connector, a broken wire, or the sensor gone open-circuit. The knock-on is real though — an ECU that thinks the engine is freezing will over-fuel it (running rich, smelly exhaust, poor economy) and the cooling fan may run flat out as a precaution. Cheap sensor, usually an easy job."
Worth checking in roughly this order. Don't jump straight to the expensive fix:
The code itself is a snapshot. The fault sets after the car's watched the numbers over a whole drive cycle. Here's what's worth keeping an eye on:
Live simulation on the readings our free demo drive supports. This is how the app’s dials move.
Codes rarely tell the whole story. The clever part is reading them together, and against your exact car. Here's the kind of thing it catches:
Same family of fault as P0113, but on the engine coolant temperature sensor: the signal voltage is stuck high, which the ECU reads as an absurdly cold engine — minus 40 territory. That's electrics, not temperature: a dodgy connector, a broken wire, or the sensor gone open-circuit. The knock-on is real though — an ECU that thinks the engine is freezing will over-fuel it (running rich, smelly exhaust, poor economy) and the cooling fan may run flat out as a precaution. Cheap sensor, usually an easy job.
For short hops, yes — but there are two catches. The engine runs rich while the ECU thinks it's cold, which wastes fuel and isn't kind to the catalytic converter. And with the sensor lying to you, neither you nor the ECU can spot genuine overheating. Fix it soon rather than someday.
The sensor itself is usually £10-30, and on most engines it's accessible enough that a garage will do it inside an hour's labour. DIY is realistic if you're comfortable losing and topping up a bit of coolant. Wiring repairs, if that's the cause, are similarly modest.
No — the engine light on is an automatic MOT fail these days, and the rich running this causes could push the emissions test over the limit too. It's a cheap fix, so sort it before the test rather than gambling.
Free app. Plug in, and get every code in plain English, plus the connections you'd never spot.