[zaiddroid]

Originally Posted by Bsilver

There is separate fan control module/relay which is present in the left lower side/passenger side near the radiator mounting points. This is responsible for controlling the fan. The part number: 1J0 919 506 M. If this is faulty then the above problem arises. This module turns faulty if a lot of water wading at high speeds is done, or there is some water entering into the bay area, at least for me the problem raised after passing through deep waters. There is a way to check this, bypass this fan control module by directly connecting the power/ground and necessary wiring directly to the fan, this will require you to splice wires and know the wiring diagrams, or if you are not able to do this, then better to get it done from a FNG. If the problem then goes away then it was the module which is faulty. Do remember that you cannot drive on this method for days together, as it will run the fan continuously which may cause it to overheat. Or an easier way is to replace this module with a known good one and check. If this also cannot be done, there is a even more complex way to do the same, if really required.

Happy Motoring!

Thank you so much @Bsilver, for the guidance and insights.

I know the position of the relay and I am not very skilled to check this. However I stay in Bangalore too - it would be great if you could please help me locally. I can bear the charges.

I have a vagcom cable and vcds lite too, is there a way to diagnose the relay problem through a computer without having to physically touch wiring? Can I DM you? Thanks

Originally Posted by hensil

Can you believe, I have the same issues with my Harrier 2022 April model. Last month the ac blower got faulty. I got it replaced under warranty. After that I learnt of the same issue as yours. Last week I went to the service center and explained them the issue. They did some general service and claimed the ac is working fine. Yesterday I came to know that the issue still persist.

I knew this was complicated to diagnose. And how would I prove about this issues to the service centre.
Tomorrow I'll go to the service center and show them this thread.

Haha so how I show this to the service center is I keep the AC running for 45 minutes or so and when the cooling goes, I show them. The problem is annoying if you don't have a knowledgeable ac technician.

Originally Posted by The Mechanic

Have you checked your condenser fan?. Sorry If I missed it somewhere in the thread.

If you have not checked, check if it is turning ON correctly and is having the required speed. Some cars have a single fan for radiator and condenser and operate at 2 speeds, while some cars have a separate fan for the condenser.

Also, when the compressor is being cut off, is any refrigerant line frozen on the outside?

The fan switches on and has 2 speeds hi speed and low speed. There is just one fan. However I’m unsure if the fan switches off when the cooling stops. I think it continues to work even if the cooling stops in low speed. I don’t know how to check this.

The refrigerant lines lose its cooling when the ac cooling stops/compressor power cuts off.

[Bsilver]

Originally Posted by zaiddroid

I have a vagcom cable and vcds lite too, is there a way to diagnose the relay problem through a computer without having to physically touch wiring? Can I DM you? Thanks

You can do an output test using VCDS. But this really would not give you rightful results. If you want to try, go to Engine--> Output tests--> Sequential/Selective-->Control Circuit for Cooling Fan.

This will make your fan run but then, how long can it run cannot be gauged. We know for the fact that it is stopping post driving for a set duration. You may need to connect a battery maintainer to the battery and then check the same, as continuous running of the fan will drain the battery, plus we are not even replicating the control side of the fan. You may have to run the test several times in order to determine the fault, albeit there is no guarantee of the same. So VCDS will run the fan for you but will not replicate the situation. It would be good if you send me a scan of the vehicle through the cable. I will DM you, since you still do not have the option, and we may continue.

Another method to check the fan, this includes the splicing of wires, but it is a cheap way to test without any extended analysis. You need to tap in the power terminal of the module, this can be determined by wiring diagram as to which side is control, power and ground. Once tapped in, you may connect a test light in parallel, and then route it all the way inside the cabin, and connect a known good ground. You can then drive the vehicle and as soon as the controller triggers the fan to turn on, the test light will light up. You should continue to drive until the issue comes, and when the issue comes the test light would not light up, and without switching off the engine or making any changes to existing conditions, you should go and check the power side of the fan control module which comes from the wiring harness, the diagram needs to be there with you for this. Take the same test light and then check if there is power supply to the control module itself. If there is still power supply to the module, then you can conclude that the module is indeed faulty, and you can then restart the vehicle and again the test light will glow. It is a long process, but will save a lot of money and no need of looking in other wirings. If all this does not happen then one needs to do more investigation.

Many would suggest, you should monitor the MVB under the engine for cooling fan activation. But I have already tried it in my case and it does not help. Hence the method.

Hope you understand what I am trying to convey.

Happy Motoring!

[zaiddroid]

Originally Posted by Bsilver

You can do an output test using VCDS. But this really would not give you rightful results. If you want to try, go to Engine--> Output tests--> Sequential/Selective-->Control Circuit for Cooling Fan.
…
Another method to check the fan, this includes the splicing of wires, but it is a cheap way to test without any extended analysis. You need to tap in the power terminal of the module, this can be determined by wiring diagram as to which side is control, power and ground. Once tapped in, you may connect a test light in parallel, and then route it all the way inside the cabin, and connect a known good ground.
…
Many would suggest, you should monitor the MVB under the engine for cooling fan activation. But I have already tried it in my case and it does not help. Hence the method.

Thank you so much @Bsilver for meeting me and diagnosing that there fan control module is not the issue. We also found out that that outside temperature sensor wire is cut ( can that be a reason?).
I got an opportunity to test the shut down code on my car as suggested by you. Turns out I’m getting shut down code 12. Both the stage fans are being switched on as well. How do I proceed with diagnosis from here. Please help me.
I also noticed that the outside temperature sensor that comes in the left part of the bumper has been cut off die to rat bite (I’m going to fix it - can that be an issue as well), Also when the car is being driven I’m getting an internal control module error. I’ve attached the images of the scan. The other errors like high pressure sensor error, etc were cleared upon clearing the codes however the internal control module error continues to pop up even after clearing after driving the car a bit.

[hensil]

It's three days now my car is in the Pune service center. The technician tried few things but couldn't rectify the problem. Now he wants to replace the compressor. This will take another 4 to 5 days. Fortunately, my car is still under warranty. From the discussion in this thread I believe the faulty is not in the compressor but somewhere else. Anyway, I have to wait.