Sensor 3 is a third oxygen sensor on bank 1, behind a second converter or converter brick. It only exists on some vehicles – documented for Jaguar Land Rover's 3.0 V6 supercharged (2013–2016, where sensor 2 is 'mid-cat' and sensor 3 'post-cat') and Ford systems that monitor part of the converter volume. P0147 concerns its heater. Ford checks the driver voltage continuously and the heater current once per drive cycle once sensor 3 is above about 120 °C and has heated for 30 s – below about 0.22–0.465 A (depending on supplier) or above 3 A counts as a fault; the heater resistance is a separate code (P0055). Jaguar Land Rover lists P0147 for its post-cat sensor. When it fails, the control module stops the downstream trim and cannot evaluate the converter; there is no limp mode.
Medium severity. Can I keep driving?Yes, you can normally drive in moderation, but get it repaired soon: you will use more fuel and the catalytic converter can be damaged over time.
Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.
Symptoms
- Check engine light on (usually after two drive cycles)
- Follow-up codes for sensor 3 possible
- Usually no noticeable change in driving
Most likely causes
- Heater element in the sensor burnt out (replace sensor)
- Heater supply (fuse, relay) or control wire open
- Connector corroded, contact resistance
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: easy
- It affects emissions.
What each character of P0147 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 1: Air and fuel
- 47: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0147?
Yes, you can normally drive in moderation, but get it repaired soon: you will use more fuel and the catalytic converter can be damaged over time.
What causes code P0147?
The most common causes are: heater element in the sensor burnt out (replace sensor); heater supply (fuse, relay) or control wire open; connector corroded, contact resistance.
Related codes
- P0042HO2S Heater Control Circuit (Bank 1 Sensor 3)
- P0043HO2S Heater Control Circuit Low (Bank 1 Sensor 3)
- P0044HO2S Heater Control Circuit High (Bank 1 Sensor 3)
- P0055HO2S Heater Resistance Bank 1 Sensor 3
- P0141O2 Sensor Heater Circuit Bank 1 Sensor 2
- P0167O2 Sensor Heater Circuit Bank 2 Sensor 3
Sources
- law.cornell.edu: 13 CCR 1968.2
- newtonnet.co.uk: fordobd2012
- fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023
- static.nhtsa.gov: SB 10096822 1020
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.