P0135 Powertrain O2 Heater Circuit (Bank 1 Sensor 1)

[Guest]

HNY to all!

 

My MOT is looming, and I have the engine management light come on, and scanning brings up: P0135 Powertrain O2 Heater Circuit (Bank 1 Sensor 1)

 

where is this sensor located, and is it an easy replacement?

[Geralt]

It's screwed into the exhaust, one of two, upstream of the cat converter. Should just require a spanner I imagine.

 

But before you buy another sensor, clear the code and swap bank 1 with 2. Ensure the diagnosis moves to bank 2. If it doesn't it could be your ECM at fault. Note it may require two drive cycles to diagnose. I'm assuming that both sensor heaters use the same fuse.

[Guest]

Thanks @Geralt

 

I'll take onboard the swapping over of sensors!

 

Will any of these part numbers be fine to replace with, if it is the exhaust sensor: 89465-0D040, 89465-05100, 89465-06030, 89465-06250, 89465-10070

[starider]

Hi, had a similar problem with my Ford Van, after much searching I found the heater ducts were blocked with leaves and crud, cleared out and management light went out. Also similar problem with a Vitara when the air intake filter became damp during wet weather and the filter needed changing,the dust etc in the filter became solidified, a new filter cured the problem and once again management light extinguished.We get an aweful amount of wet weather!!

Hope this helps,in both cases a simple fix.

[Geralt]

6 minutes ago, AlphaMZ said:

Thanks @Geralt

 

I'll take onboard the swapping over of sensors!

 

Will any of these part numbers be fine to replace with, if it is the exhaust sensor: 89465-0D040, 89465-05100, 89465-06030, 89465-06250, 89465-10070

That I do not know sorry. I just used to work in engine management software but don't have any knowledge of the Alphard in particular. I'm confident someone here will know which part to get.

[Geralt]

15 minutes ago, AlphaMZ said:

Will any of these part numbers be fine to replace with, if it is the exhaust sensor: 89465-0D040, 89465-05100, 89465-06030, 89465-06250, 89465-10070

I guess it could be either of these two:

 

https://www.autojapspares.co.uk/toyota-alphard-mnh10-15-30-v6-petrol-2002-08-lambda-oxygen-02-sensor?search=alphard lambda&category_id=0

 

https://www.autojapspares.co.uk/toyota-alphard-anh10-24-petrol-2002-08-rear-lambda-oxygen-02-sensor?search=alphard lambda&category_id=0

 

I guess front and rear translate to Bank 1 or 2. In principle there should not be any difference between bank 1 and 2 so the difference could be harness length or the connectors might be different for poka-yoke.

 

Maybe give them a call with the P-Code and they could advise which one to buy?

[Guest]

perhaps the 2.4 and 3.0 models are different part numbers; I've a 3.0l 2007 model!

[Geralt]

1 minute ago, AlphaMZ said:

perhaps the 2.4 and 3.0 models are different part numbers; I've a 3.0l 2007 model!

The URL is misleading. If you search for "Alphard Lambda" and click on the following...

 

 

...it takes you to the 2.4L part. We can infer then that the 2.4L lambda sensor (there's only one) is the same part number as the 3.0L rear sensor....or they might have made a mistake. Either way I think you need to check with them if you need front or rear.

[Picasso]

Alphard 3.0 sensors are the same front and rear 2.4 alphards have a fuel ratio sensor on the front and a lamba sensor on the rear do you by any chance have a lpg conversion fitted 

 

 

 

 

 

 

 

 

[Guest]

1 minute ago, Picasso said:

do you by any chance have a lpg conversion fitted 

no LPG fitted! 

[Picasso]

OK I had similar problem my advice to you would put a good cat cleaner adidative in the fuel and give it a good blast this will clean the lamba sensor it cured mine 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Guest]

1 minute ago, Picasso said:

put a good cat cleaner adidative in the fuel and give it a good blast this will clean the lamba sensor

thanks for this input; which one do you recommend?

[Picasso]

Forte is a good product I buy it from my local motor factor's or a product called cat cleaner halfords will sell it best to mix with quarter tank of fuel 

 

 

 

 

 

 

 

 

 

 

[Picasso]

Do you do much milage or is it mostly stop start driving 

 

 

 

[Guest]

I have 2 motors, but the Alphard I mainly use in good weather, so around 400 a month, with a minimum of 20 miles to the nearest town!

[Guest]

On 1/8/2023 at 9:59 PM, Picasso said:

cat cleaner halfords will sell it best to mix with quarter tank of fuel

didn't cure the issue for me, so ended up replacing the 'front' sensor Monday past, and is now free of the error having cleared the fault code, and staying off!

[Geralt]

23 minutes ago, AlphaMZ said:

didn't cure the issue for me, so ended up replacing the 'front' sensor Monday past, and is now free of the error having cleared the fault code, and staying off!

Thanks for telling us the outcome. Good to know.

[Guest]

spoke too soon; the EML has come back on again having replaced the FRONT sensor, so I question if it really is the Front sensor afterall, as it's a new unit?

[Geralt]

41 minutes ago, AlphaMZ said:

spoke too soon; the EML has come back on again having replaced the FRONT sensor, so I question if it really is the Front sensor afterall, as it's a new unit?

Same P code?

[Guest]

Thanks for your response @Geralt, yes, same code!

[Picasso]

Maff sensor brings up same code 

 

[Geralt]

11 minutes ago, Picasso said:

Maff sensor brings up same code 

 

What would be the thinking behind that?

[Geralt]

1 hour ago, AlphaMZ said:

Thanks for your response @Geralt, yes, same code!

You probably have the right sensor but to make absolutely sure, disconnect the other sensor. You should get additional P-Code(s), possibly P0141, if you have identified the correct sensor.

 

The P-code is saying the heater circuit is faulty so that potentially includes a high resistance anywhere from ECM circuit board or relay through the connectors and harness. Have you checked all the fuses? Check any harness connections all the way to the ECM connector. Examine for corrosion on the connector pins, clean with contact cleaner if looking dodgy. The resistance of the heater circuit should be less than 10 ohms or thereabouts, if it's much higher then there's a broken cable somewhere.

 

Once you've checked all those then the only likely candidate is the ECM. I can see some on ebay but it is possibly complicated by immboliser codes and such so may not be plug and play. Maybe someone has replaced theirs on this forum.

[Guest]

Thanks for that info @Geralt. I'll get my mechanic onto the job asap, as the MOT is a week Monday!

[Guest]

where's the oxygen sensor fuse located?