Hi to everyone,
Is just a month that i own my j11, but i remember that when i use to switch the car off with ac on, when i restart the car, ac goes on again automatically. I had to bring car to Bosch car service 10 days ago to change the post cat 02 sensor, and after that ac does not go on automatically at reatart. Ac work perfectly, the only issue is that when i switch car kn i have to manually switch ac on....i tried to disconnect battery for 20 mins and even scan it for any error but nothing. Maybe any kind of hided settings or procedure to make it working again?
Ac unit does not goes on at restart
- calnorth
- Posts: 2719
- Joined: Mon Feb 11, 2019 2:01 pm
- Qashqai Model: Mk.2 Qashqai Facelift - J11b (2017–2021)
Is the Aircon button illuminated when you start up and engine running? Meaning that the Aircon is initiated and apart from the cooling system (compressor etc) working.
Mk2 Qashqai Facelift - J11b (2017–and onward)
1.6 Dig-T N-Connecta
1.6 Dig-T N-Connecta
- calnorth
- Posts: 2719
- Joined: Mon Feb 11, 2019 2:01 pm
- Qashqai Model: Mk.2 Qashqai Facelift - J11b (2017–2021)
ok...its difficult to tell whats wrong and I can't see that the O2 sensor is a problem. Of course we don't know what the Bosch agent did ...exactly.
The Aircon system schematic is as shown below. I can only guess that the ECM/IPDM cpu may hold state memory as regards the Aircon button. I am looking at A/C ON, Blower fan ON which enables command via the ECM to the Compressor. This is CAN Bus comms. The question is what might an O2 sensor have to do with that?
You may need to ask Bosch what they have done exactly and what procedure they used to install a new O2 sensor.
Mk2 Qashqai Facelift - J11b (2017–and onward)
1.6 Dig-T N-Connecta
1.6 Dig-T N-Connecta
I also guess that is like a kind of "storage value" fault...i suppose that the problem could be like a kind of deep reset of the ECM. They said only did a scan and o2 sensor error clearing....but when i get car back ,all settings was back to factory....
- calnorth
- Posts: 2719
- Joined: Mon Feb 11, 2019 2:01 pm
- Qashqai Model: Mk.2 Qashqai Facelift - J11b (2017–2021)
Attached is the HAC unit diagnostics but it will require Nissan special tools:
- HAC+-+HEATER+&+AIR+CONDITIONING+CONTROL+SYSTEM.pdf
- (3.23 MiB) Downloaded 127 times
Mk2 Qashqai Facelift - J11b (2017–and onward)
1.6 Dig-T N-Connecta
1.6 Dig-T N-Connecta
- calnorth
- Posts: 2719
- Joined: Mon Feb 11, 2019 2:01 pm
- Qashqai Model: Mk.2 Qashqai Facelift - J11b (2017–2021)
Its difficult to know exactly where the AC button state is held. It enters the AC Auto Amp via LIN Bus and processed within. So it may be reserved there or further on at the ECU etc? The diagnostics may have a setup procedure...there is a lot of detail there. The test/configuration tool is Nissan Consult which is not freely available.
If the battery was disconnected for 30 mins or longer perhaps a reconnect might default certain functions. I think thats about all you could do.
Mk2 Qashqai Facelift - J11b (2017–and onward)
1.6 Dig-T N-Connecta
1.6 Dig-T N-Connecta
I readed the pdf and for what i can understand, is not going to be an easy fix! I have already disconnected the battery for over than 30 mins with no luck... Il will keep a better eye on all fuse and relays in the front boot just in case.calnorth wrote: ↑Sun Aug 16, 2020 1:21 pmIts difficult to know exactly where the AC button state is held. It enters the AC Auto Amp via LIN Bus and processed within. So it may be reserved there or further on at the ECU etc? The diagnostics may have a setup procedure...there is a lot of detail there. The test/configuration tool is Nissan Consult which is not freely available.
If the battery was disconnected for 30 mins or longer perhaps a reconnect might default certain functions. I think thats about all you could do.
- calnorth
- Posts: 2719
- Joined: Mon Feb 11, 2019 2:01 pm
- Qashqai Model: Mk.2 Qashqai Facelift - J11b (2017–2021)
I'll have a look at the AUTO button today since I've never really inspected the system closely as regards its operation. The system logic I've never studied closely. I would normally avoid having a/c switching on automatically...open windows usually.
The diagnostics and schematic and circuit diagrams is all we have...may not be upto date?
Mk2 Qashqai Facelift - J11b (2017–and onward)
1.6 Dig-T N-Connecta
1.6 Dig-T N-Connecta