Dreaded VSC light is back after 2yrs of fault free driving

[mk_lon]

Hey Guys,

I hope all is well, I am a big fan of this forum as it has helped me massively over the last two years of being a proud IS250 owner. I was driving home yesterday and the dreaded VCS light came on, no difference in driving by the way as I was on a dual carriage way (No limp mode or anything).

I connected my OBD2 reader and found 2 error code  the first is P0031 HO2S Heater control circuit Low Bank 1 Sensor 1 - which is worrying as I put a new denso oxygen sensor in bank1 sensor 1 in sep15 (after code of P2195). The second said No codes are stored in the module! 

Before I take it to my Independent garage, I thought Id get some advice from you guys as a starting point.

Kind Regards,

Mo 

 

[mk_lon]

Thought I'd add some images. Thank you in advance :)

[bobmc]

Sounds like the heater circuit has failed in the sensor, despite it being just over 2 years old. Easy enough to check for sure with a multimeter. 

[KenMavor]

23 minutes ago, bobmc said:

Sounds like the heater circuit has failed in the sensor, despite it being just over 2 years old. Easy enough to check for sure with a multimeter. 

Would agree with this...was it an OEM or aftermarket sensor?

It maybe that it just needs a damn good clean....have you checked the wiring as well?

Would agree to get a multimeter on the system to try and see where the fault lies.

 

[normski2]

It's the easiest one to get at....that's a bonus.

Try unplugging from the connector. Check the pins are straight and have a visual of the wires. Reconnect and at the least you can cross that off your check list.

 

[mk_lon]

Thanks guys, I bought a brand new denso (OEM) in sep 15, so its surprising that it would fail. Although I'm a little confused onto why there are 2 errors.

I don't own a multi meter and probably would'nt know how to check, I suspect its a trip to the local independent garage who I usually use  

[bobmc]

basic multimeter only costs around £10 and is a useful bit of kit to have round the house.

connect the meter across pins 1 and 2, you should get reading of about 2 to 4 ohms otherwise it's a failed sensor. The meter can also be used to check the fuse and that 12v is getting to the sensor.

 

 

[mk_lon]

Thanks bobmc,

I'll defiantly look into it, makes sense to have one around the house.

 

 

[mk_lon]

Hey Guys,

Something strange happened to the car on Saturday morning, the VSC light(s) disappeared. I drove today and the light still hasn't come back on. I ordered a new oxygen sensor and it arrived as per the instructions of my local indy garage and was booked in for Tuesday. 

I took the car on the a406 today for a spin for about 45mins, when I got back and turned the engine off I noticed a small amount of smoke coming from the left exhaust......

I'll probably cancel the trip to the garage on Tues and wait until the lights re appear and probably hold on to the oxygen sensor for a bit .....Not sure what to make of all this?

 

 

[ColinBarber]

Unlike most error codes, ones relating to the O2 heater circuits are very reliable. It is easy for the ECU to tell if the circuit is complete or not.

Unplug and check the connector for corrosion/water, and check the cable for damage. As stated above you can check the resistance on the sensor side of the connector (pins 1 and 2), and 12v on the engine side of the connector. It is unlikely to be a 12v supply issue though, the fuse and relay that provides this serves both sensors so you would expect to see both P0031 and P0051 if that was the problem.

[mk_lon]

Hi Colin,

Thanks for the insight. I'll check it out tomorrow hopefully, it might be a faulty cable or something. 

 

[madasahatter]

On 2/20/2018 at 3:03 PM, mk_lon said:

Thought I'd add some images. Thank you in advance :)

Mine has the same code where did you purchase the sensor from.

[mk_lon]

I bought it from import car parts, £105 delivered. I called Lexus and they wanted £200. 

https://www.importcarparts.co.uk/

[mk_lon]

Worth mentioning that light is back, but due to the cold I haven't had a chance to open the bonnet.

[dazed]

On ‎25‎/‎02‎/‎2018 at 5:32 PM, mk_lon said:

I took the car on the a406 today for a spin for about 45mins, when I got back and turned the engine off I noticed a small amount of smoke coming from the left exhaust......

 

It might just have been the final moist exhaust gases wafting out - more likely to be visible in cold weather.

[normski2]

9 hours ago, mk_lon said:

I bought it from import car parts, £105 delivered. I called Lexus and they wanted £200. 

https://www.importcarparts.co.uk/

Useful place to know of ... bookmarked it ... thanks. 

[madasahatter]

Just now, normski2 said:

Useful place to know of ... bookmarked it ... thanks. 

I have payed £110.00 delivered from world car parts. Did you remove the ecu when you replaced yours? I am going to see if i can do it from a pit at work.

Take the covers off underneath and see if its possible.Main problem i can see is the angle of the sensor.

[Texas]

11 minutes ago, dazed said:

It might just have been the final moist exhaust gases wafting out - more likely to be visible in cold weather.

These cars do tend to emit smoke or 'steam' even after prolonged use unlike most other cars and it was discussed here concerning an MOT testers interpretation of what it is!

 

[madasahatter]

The Skoda Vrs i owned before this, looked like it had caught fire at the lights. I think with the Lexus having twin pipes exaggerates the situation.

Pretty cool all the same though. 

[normski2]

1 hour ago, madasahatter said:

I have payed £110.00 delivered from world car parts. Did you remove the ecu when you replaced yours? I am going to see if i can do it from a pit at work.

Take the covers off underneath and see if its possible.Main problem i can see is the angle of the sensor.

Yes I did remove the battery/ecu etc. It is incredibly tight to get in and at the sensor. You can just about squeeze a hand in there, but then you can't see anything as your hand is obstructing everything. Noobies description of how to do it is ***** on. It was also the hardest sensor to budge. Thought the darned thing was welded in it was so tight. Had to use a piece of pipe on the socket handle to get the leverage. Working from underneath is going to be tricky. I'd say you can do it from topside in 2 hours or so. 

These 2 posts should cover it all for you

Cheers

Keith

[mk_lon]

5 hours ago, dazed said:

It might just have been the final moist exhaust gases wafting out - more likely to be visible in cold weather.

Yea, makes perfect sense. I looked it up and its pretty common

[mk_lon]

Hey Guys,

Quick update - I took it to my local Independent Garage and they changed the Oxygen Sensor. Since then the light has gone and the car is back to normal. The light had re appeared a few days ago and the car was noticeably slower and sluggish. 

Really annoyed that the sensor (from denso) only lasted 2.5 years!!

 

 

[normski2]

Sounds like you've just been unlucky with that sensor as Denso gear is decent quality in my findings thus far.

I guess anyone can have a Friday afternoon slip up from time to time!

[ColinBarber]

5 minutes ago, normski2 said:

I guess anyone can have a Friday afternoon slip up from time to time!

Indeed, or it was a fake one.

[mk_lon]

6 hours ago, normski2 said:

Sounds like you've just been unlucky with that sensor as Denso gear is decent quality in my findings thus far.

I guess anyone can have a Friday afternoon slip up from time to time!

Yea I think so too, worth mentioning that my local Indy garage said that in the last 20 years or so, they have noticed most of the aftermarket car parts (all makes) no longer last as they used to.