P0031, P0051, P0057 and P0102 codes on 2008 RX400h

[Rutlandlex]

That's great news Clive thanks for letting us all know.  I wonder how much that would have cost at a stealer with double labour rates and changed parts that weren't really needed.  I would imagine that the fuse blew as a result of the damage to the wiring causing a short circuit either between the 2 wires or the positive wire could have touched the body of the O2 sensor which is negative.  It only takes a split second of contact to blow the fuse.

[ColinBarber]

If the petrol engine isn't shutting down correctly then there is an initialisation procedure that needs to be performed after the 12v Battery is disconnected. A search on these forums should find the solution.

[Clive-D]

14 hours ago, ColinBarber said:

If the petrol engine isn't shutting down correctly then there is an initialisation procedure that needs to be performed after the 12v battery is disconnected. A search on these forums should find the solution.

I don't think that was a problem - the engine kept running rough on tickover when I had the error codes. It is stopping as I would expect now, after the repairs. The Battery was replaced March 2017 and hasn't been disconnected since. Surely the problem would have been there when I got an engineers report before I bought the car ? There's a lot of talk here about 12v Battery issues, so it seems they can be problematic.

[ColinBarber]

4 hours ago, Clive-D said:

I don't think that was a problem - the engine kept running rough on tickover when I had the error codes. It is stopping as I would expect now, after the repairs. The battery was replaced March 2017 and hasn't been disconnected since. Surely the problem would have been there when I got an engineers report before I bought the car ? There's a lot of talk here about 12v battery issues, so it seems they can be problematic.

I was commenting on the behaviour you stated after the repair:

Quote

On the short drive back, the hybrid battery went from very run down to very well charged - green, one bar from the top. A bit early to say, but it felt like the hybrid system was charging more than needed and the consumption was lower than I'd expect in town driving.

 

[Clive-D]

Latest update... !

I got a return of the error codes after a couple of days - O2 sensor circuit low/high voltage Bank 1 Sensor 2, codes P0137/138, then more - so I got the car back to the  guy. He said there were loads of codes which he cleared. He did a long test run and said the can ran beautifully with no problems. Suggested I leave the dongle unplugged as they can throw error codes but if I keep getting O2 sensor error codes it's likely I'll need to replace it. The car is running fine but every 2nd or 3rd start up, the engine light will come on during a journey, always the same, which I stop and clear, then it's fine again for a while, so I going to replace the sensor.

Anyone got any experience of replacing sensor 2 in Bank 1? I'm quite competent if it's accessible. Otherwise its back to the garage. What is an OEM part number?

Thanks. Nearly got this sorted.

[BachelorDays]

Each bank has two sensors - pre and post CAT.  Sensor 2 is post CAT so access is from underneath the car and many times partially obstructed - although not inaccessible.  Most of the times the problem is getting the years old jammed sensor unscrewed.  Should otherwise be plug and play.

You could initially just undo the connector underneath and secure it against the elements then run the car for a few days.  You'll get the O2 sensor codes (bank 1, sensor 2) but no other codes.  That's one way of checking if it's just the sensor.

Don't know what you mean by the Dongle comment.

[Clive-D]

3 hours ago, BachelorDays said:

Don't know what you mean by the Dongle comment.

It's the electrician's word for the OBD II reader!

3 hours ago, BachelorDays said:

You could initially just undo the connector underneath and secure it against the elements then run the car for a few days.  You'll get the O2 sensor codes (bank 1, sensor 2) but no other codes.  That's one way of checking if it's just the sensor.

I'm not getting any other codes now, so I'd just get the same code doing what you suggest. I read it is best to replace both if you have an error on one bank - sensor 1 pre cat and sensor 2 post cat. The logic being that if sensor 2 has failed and is replaced, sensor 1 whilst it may still be working ok may not be in sync with the new sensor and throw up an error (think that was the gist of it).

Anyone got experience of fitting these as the price variation is huge. With an older car I don't need one to last another 10 years, but equally don't want to create problems by fitting a cheap poor functioning one!

[BachelorDays]

Sorry, I thought you did have other codes coming in too.  Otherwise it most likely is a fried sensor because of the shorted wiring so good idea to replace it.

Pre and post CAT sensors are not in sync.  The Pre sensor reports on the richness or otherwise of the gases produced by combustion, primarily affecting the air/fuel mixture upstream.  The Post sensor reports on the efficiency of the CAT.  So no sync between the two.  

I know what you mean about the pricing.  I'd start a new thread about recommendation on a Post CAT sensor.  There are some very reasonably priced options on eBay - but only someone who's used one of these will be able to give definitive advice.  I'd even look at a used one - but only if I was going to do the installation myself.

[m4rkw]

@Clive-D Just my 2 cents but I’d want something a bit more concrete than “likely” before throwing another part at it. Perhaps ask the guy if there is anything else that could cause the same symptom that you could rule out with some diagnostics? 

[Clive-D]

2 hours ago, m4rkw said:

@Clive-D Just my 2 cents but I’d want something a bit more concrete than “likely” before throwing another part at it. Perhaps ask the guy if there is anything else that could cause the same symptom that you could rule out with some diagnostics? 

Good point (and BatchelorDays), but the error code P0137 is very consistent (Sensor circuit low voltage Bank 1 Sensor 2). If i wait to clear it I may also get P0138 (Sensor circuit high voltage Bank 1 Sensor 2). Always the same sensor. Worth asking if it's the same one with the damaged wiring. Pic attached.

[Rutlandlex]

Those wires look like they have been trapped by something or have been rubbing.  I think it is likely to have damaged the lambda sensor if the wires were shorted out even if the fuse blew which it did.  Check out the causes in this article: https://www.obd-codes.com/p0137

Can your garage or a specialist do any testing on the sensor to determine if there is internal damage?  This article explains in great detail how to diagnose issues with these sensors although it is aimed at garages not Joe Public but interesting nevertheless.  https://www.hella.com/hella-tech-world-us-en/lambda-sensor-2826.html

[Burroo 67]

On 9/14/2018 at 6:43 PM, Clive-D said:

Hi Colin - battery replaced March 2017 by previous owner, just before I bought the car (RAC £125 fitted, gulp!!)

Cleaner arrived today. The sensor was dirty so hopefully I have sorted the problem as it is now nice and clean. I read online the engine light should go out after about 20 miles. Is this correct, or do I need to disconnect the battery to reset the warning light (not keen to do that as I suspect I'll lose all my Satnav and radio tuning, or is that not the case? Happy to try driving to see if that clears the engine light.

Thanks for your help guys.

After reading your problems I ordered a MAF cleaner myself as I've noticed the petrol engine kicking in more than it used to, but I can't get the connector to the MAF sensor to disconnect??  TBH I didn't want to force it off in case I loosened some of the wires, did you have this problem?

[Clive-D]

On 12 October 2018 at 9:04 AM, Burroo 67 said:

After reading your problems I ordered a MAF cleaner myself as I've noticed the petrol engine kicking in more than it used to, but I can't get the connector to the MAF sensor to disconnect??  TBH I didn't want to force it off in case I loosened some of the wires, did you have this problem?

Hey sorry, missed this. (The sensor sits right on top of the engine at the back near the windscreen.) The connector has two tabs, one on top, one underneath which is a bit of a fiddle. If you squeeze on them and wiggle the connector up and down gently as you pull back it will disconnect quite easily. There are vids on You Tube. Good luck!

[Clive-D]

So to close this topic, one error keeps coming back, P0138, O2 Sensor Circuit High Voltage Bank 1 Sensor 2. I was advised this would need replacing if it kept re-occuring, which it does, so I'm starting a new thread for advice on how much to spend on one as they vary from about £30 - £150.00. As the car is 10 years old I don't necessarily need one to last 10 years so long as it functions as it should. I'll share the link to the discussion.

Cheers guys for all your help. Still managing almost 32 mpg average which is good in cold weather.