geostation
Member Since: 19 Nov 2018
Location: Buckinghamshire
Posts: 11
  
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| Fault Code P0056: HO2S Heater Control Circuit - any advice? |
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For several months my 2005 4.4L V8 D3 has displayed an orange engine warning light and the following from OBD2/Torque:
Pending Fault Log
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P0056: HO2S Heater Control Circuit (Bank 2 Sensor 2)
The car performs perfectly, with no impact upon power and fuel economy (I record every fill-up in a spreadsheet). My local garage (not a LR specialist but he does drive D4) said nothing to worry about but didn't suggest a fix.
As far as I understand it, this is telling me an O2 sensor heater control near the catalytic converter has failed; not that there's anything wrong with the cat or engine management.
Has anyone else experienced this or know specifically what needs fixing? The only post on the forum mentioning P0056 suggests a missing fuse (F11) which when fitted or replaced results in the engine warning light going out and code disappearing; but I don't seem to have a problem with F11.
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 17th Oct 2020 6:33 pm |
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Pete K
Member Since: 15 Jan 2016
Location: GL
Posts: 10773
 
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One of the 4 oxygen sensors probably needs replacing.
You should be able to measure resistance to confirm and find which one.
Once warmed up should be fine
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| 17th Oct 2020 7:41 pm |
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Globetrotter448
Member Since: 21 Mar 2017
Location: Londonderry NSW
Posts: 1826
 
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Indicates LH side of vehicle and rear sensor on that side.
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| 19th Oct 2020 7:09 am |
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geostation
Member Since: 19 Nov 2018
Location: Buckinghamshire
Posts: 11
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| Fault Code P0056: HO2S sensor now replaced |
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Thanks for your responses, which concurred with the OBD code.
The intermittent nature of the code eventually became persistent, therefore an impending MOT failure on emissions.
I looked up the part in the workshop manual for confirmation and did consider DIY but lack of a good workshop and cold winter weather convinced me to ask my local garage to replace it.
Part, labour & VAT: £162 in total.
Nice to have a dark dashboard again when the engine is running!
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| 14th Jan 2021 12:42 pm |
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