Hey Mr Scotty!
Xterra S 2011 Automatic, 116k mileage. Since a few days, its AC cooling stops as soon as I switch to the reverse gear. It works perfectly fine in all other gears, N, D and even P. I ran the diagnostic mode and the motor fan is also running fine. I had the gas refilled just before this problem occured. Any ideas why it is behaving so?
Correction above: it is 116k KMs not miles.
Thanks!
Start with load testing the battery and alternator.
Battery Alternator look fine.
When you ran the IPDM auto active test were the cooling fans running in both Low and High speeds?
Test should cycle through:
Low speed for 5 seconds
High speed for 5 seconds.
I performed the IPDM test based on this video and it ran exactly like in the video. The AC clutch turned on and off and the fan was working too, didn't notice High or low speed in test.
The cooling in all other modes is perfect. There is no complaint of less cooling or airflow, it is just that in reverse gear it just throws normal air instead of cool. Even in P and N it cools as it should.
Yeah but have you looked up how the computer, through the IPDM, controls the fans?
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I was working on the AC of an Altima a while back and I looked at the system description before I started
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It's based on: AC on, engine coolant temp as well as rpms, and vehicle speed
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In your case, get somebody else to reverse the car until the AC stops cooling and then hold their foot on the brake (in reverse) as you pop the hood and check to see if the cooling fans are running on high
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Unless you're travelling at a high speed the fans should be running on high when the AC is on
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If they're running on high, maybe your condenser is dirty
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Try hosing it off but be careful. The aluminum fins bend easily and a garden hose at full blast is enough to bend them
.
Okay, will check that one up and post here with the update.
The AC Clutch seems to turn off when the gear is switched to Reverse and then back on when in any other mode. The fan speed doesn't change at all.
Battery also replaced (was due anyway) but no effect. Still not cooling in reverse gear.
I have to ask - How did you discover this? How much driving in reverse do you do, and why?
I gave it to Nissan service for regular servicing, they said I had an AC hose leak(AC in reverse is working at this time). So I went to a private mechanic who is known to my friend, who repaired the hose and refilled the gas. Ever since then it stops cooling in reverse. Those mechanics wont accept they did anything wrong. And I noticed it instantly coz the temperatures at my place is like 118 to 120 F in peak summers with humidity, and me being a heavy sweater, get all drained in sweat in seconds.
I dont have to use reverse all the time, but it is just that something is wrong with the system and it keeps bothering me that eventually it will cause the whole ac system to break down.
Still looking for a solution.