[NPV]

Originally Posted by fusionbang

Let it be for couple of days, it will go away on its own. That's what happened on my safari and I had spoke to my SA that I will be taking the car over the weekend. Then I did not have to use the car for couple of days and the error vanished on its own.

Also, it could be because of the soot accumulated. Try either of the below and see if it helps, else you might have to take it to the service center and get it checked.

1. Try to race the engine in neutral above 2500 rpm for few minutes and the error should go away.

2. Try running the car above 60kmph and above 2500rpm for 20 mins or so, if you have easy access to the highway.

This is what gets my Goat - In most cars, the Check Engine Light is something that will glow only if there is something serious that needs to be checked in the vehicle. I'm quite appalled now to see it has become a farce especially with Tata vehicles, I hear these things on the owners group as well - leave it for couple days and it goes away or restart the car after 10 minutes and it goes away, heck on one Facebook Harrier owners group someone mentioned open the fuel tank cap to let the "gas" out, close it and then restart the car, the check engine light will go away (for this very same error I'm seeing)

Unless the whole BS 6 roll out with DEF etc has caught them unawares and the ECU is throwing up these false alarms (which is also not acceptable anyways), I don't understand why they happen frequently.

Also, my car is running on the highway about 95% of the time and hardly sees any city runs.

I will restart the car tomorrow (it will be 2 days after the error indication) and see what happens. If it does not go away, I've anyways called the service centre and booked a slot to run diagnostics and have it checked (I prefer this for peace of mind).

[NPV]

Originally Posted by NPV

Drove the car to the service centre today.
On running diagnostics, found a memorised error - “NOX sensor wire failure”.

Originally Posted by NPV

This morning I’m seeing the check engine lamp staying on! I ran diagnostics on the iRA app and this is what I see:

Drove the car to the service centre and diagnostics shows “NOX Sensor upstream open wire failure - Component Failure” with status “confirmed”, waiting for the Lead Technician here to tell me what the resolution/next course of action is.

[Kosfactor]

Originally Posted by NPV

Drove the car to the service centre and diagnostics shows “NOX Sensor upstream open wire failure - Component Failure” with status “confirmed”, waiting for the Lead Technician here to tell me what the resolution/next course of action is.

Deja Vu!

It's probably an expensive part, in any case have them replace it.

Hope you are not using any diesel additives or oil additives etc.

Originally Posted by NPV

Drove the car to the service centre today.
On running diagnostics, found a memorised error - “NOX sensor wire failure”.

On inspecting the NOX coupler and harness, there wasn’t any cut or other visible damage, so it was just cleaned with some spray and fixed back. After this a 20 minute OBD routine was run to check other errors and clear this error.
Now that it has gone away, they’ve asked me to watch if it comes back after about 100-200km of highway driving (they expect it will not appear). If it does crop up again, the next course of action is probably to replace the NOX sensor.

[NPV]

Originally Posted by NPV

Drove the car to the service centre and diagnostics shows “NOX Sensor upstream open wire failure - Component Failure” with status “confirmed”, waiting for the Lead Technician here to tell me what the resolution/next course of action is.

The service centre team said their standard procedure of verifying the NOX sensor wiring related errors is to remove the connector/coupler, check the contacts, check the wiring for any damage and then use a spray to clean, re-fit and scan again. If the error goes away, it should be fine. Following this procedure, the error went away, so I took the car on a test drive with the technician and found everything to be fine.

However, this was the second time in 14 months of ownership that the same error had shown up and the same process to “fix” was followed (strangely the errors had popped up exactly 7 months apart!). I had screenshots from the iRA App from both instances, but no pictures of the scan tool showing the error (service centre insists on a no photos policy), and I wanted to have this documented so that if the need arises I can claim it under extended warranty. I requested the service centre to open a job card and mention the NOX error in the remarks. They did seem a bit reluctant and gave excuses like “it will not be a problem and all authorised Tata service centres will replace the part if they determine it has failed”, then they switched to “it will take a lot of time to open the job card”. I calmly stood my ground and requested them to do it, and they finally relented. Gave me some peace of mind!

Originally Posted by Kosfactor

Hope you are not using any diesel additives or oil additives etc.

No, I’m not using any additives, in fact the manual clearly mentions this car should use normal diesel only so I never use power diesel.

[Kosfactor]

Originally Posted by NPV

However, this was the second time in 14 months of ownership that the same error had shown up and the same process to “fix” was followed (strangely the errors had popped up exactly 7 months apart!). I had screenshots from the iRA App from both instances, but no pictures of the scan tool showing the error (service centre insists on a no photos policy), and I wanted to have this documented so that if the need arises I can claim it under extended warranty. I requested the service centre to open a job card and mention the NOX error in the remarks. They did seem a bit reluctant and gave excuses like “it will not be a problem and all authorised Tata service centres will replace the part if they determine it has failed”, then they switched to “it will take a lot of time to open the job card”. I calmly stood my ground and requested them to do it, and they finally relented. Gave me some peace of mind!
.

Good you did that because BS6 after treatment bits are very expensive in all vehicles and NOX sensor particularly is a very expensive part unlike the O2 sensors in older cars.

What they meant is that all service centers will have to replace it because it's a regulatory emissions part - but just not them because they don't want to go through the process and file a claim for warranty with Tata

[NPV]

Originally Posted by NPV

However, this was the second time in 14 months of ownership that the same error had shown up and the same process to “fix” was followed (strangely the errors had popped up exactly 7 months apart!). I had screenshots from the iRA App from both instances, but no pictures of the scan tool showing the error (service centre insists on a no photos policy), and I wanted to have this documented so that if the need arises I can claim it under extended warranty. I requested the service centre to open a job card and mention the NOX error in the remarks. They did seem a bit reluctant and gave excuses like “it will not be a problem and all authorised Tata service centres will replace the part if they determine it has failed”, then they switched to “it will take a lot of time to open the job card”. I calmly stood my ground and requested them to do it, and they finally relented. Gave me some peace of mind!

It’s 3.0 now with the Check Engine (MIL Malfunction Indication Lamp) coming back this morning and the iRA App diagnostics shows the same fault “Drive train status”, I think the NOX sensor is really bad and needs replacement!

Also checked the DEF status on instrument cluster and it shows DEF Level and Quality as Ok, level approximately at 70%, which seems par for course as far has run 3000+km since last DEF top up during last service.

I have some other commitments and won’t be able to get the car checked at the service centre till mid next week, but glad that I won’t be using the car.

[NPV]

Originally Posted by NPV

I have some other commitments and won’t be able to get the car checked at the service centre till mid next week, but glad that I won’t be using the car.

Yesterday I dropped off my Harrier at the service centre for warranty claim replacement of NOX sensor.

Got an update today that the part will be arriving tomorrow. I was told they will need the vehicle to be there yesterday itself since they need to run diagnostics, take pictures and provide all necessary documentation when filing the warranty claim with the Tata Motors Helpdesk.

Hope to get the vehicle back by Saturday. Also, it seems like part number is different in the current (2023 facelift) model Vs my 2023 Pre facelift model.