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Discussion Starter #1
I have a 2020 Altima Platinum. Remote start turns on the climate control, but it doesn't turn on the heated seats or steering wheel, even if they were turned on prior to last shutting off the engine. Is this normal?
 

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Unfortunately, yes. For some reason the new HVAC's don't remember the seat heater setting when the ignition is switched off. That was never an issue on the gen5's because the switches were electromechanical, not electronic like the new gen6. The wheel heaters have never had a memory and still don't.
 

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Wow, that is the lousiest thing ever. But thanks for confirming. I'm guessing there's no workaround?
 

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I'm planning to ask our TSR about it on his next visit, since I've heard the same complaint from several people. It should be a firmware issue, but many Nissan HVAC's are set up like BCM's, CAN-readable but not CAN-programmable. I don't know if the new Alties fall into that group. If reprogramming them is possible, we may get an update.
 

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Discussion Starter #5
Got it. Please let us know what you find out, I'm sure many folks out there would greatly appreciate it!
 

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Update: I've combed the ESM and I just heard back from our TSR, who is very good. There's no way to reconfigure the seats to come on. The way the system is wired, it should be possible to use a couple of relays and a separate switch to turn them on full blast during RES, but you'd have to remember to turn the switch on or off depending on the expected weather. It would probably void the seat warranty as well, so you'd probably want to wait till it's expired before modifying anything.
 

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Just this morning with the temp at 40 degrees. I used the remote start. The seat, steering wheel, and rear window defroster were on and activated. Just as a note they were not set the night before when last I exited the car.
2019 SL AWD
 

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Wow, bizarre. The ESM didn't actually say anything about it, I combed several sections. I also checked several cars on the lot and none switched on, but I'm sure the temp was above 40. Evidently there's a thermostatic function in the HVAC firmware that isn't documented anyplace. I'm actually at Nissan School in Dallas right now for a "new tech" course, I will definitely bring this up with the instructors. Thanks very much for the info!
 

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Discussion Starter #10
Interesting, I wonder if the heated seats are programmed to activate when Remote Start is used below a certain temperature?
 

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Interesting, I wonder if the heated seats are programmed to activate when Remote Start is used below a certain temperature?
Yes, that's what I meant by "thermostatic". The car has both ambient and cabin temperature sensors, so it does know how cold it is outside and inside. I'm just flabbergasted that there isn't a word about it in the service manual. I asked two of the instructors today and they didn't know either. I'll keep digging, but it may be that the only ones who know are the programmers at Calsonic who coded the HVAC.
 

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Discussion Starter #12
Yes, that's what I meant by "thermostatic". The car has both ambient and cabin temperature sensors, so it does know how cold it is outside and inside. I'm just flabbergasted that there isn't a word about it in the service manual. I asked two of the instructors today and they didn't know either. I'll keep digging, but it may be that the only ones who know are the programmers at Calsonic who coded the HVAC.
Gotcha. You’re right, one would expect the manual to state that the heated seats will activate if remote is used below X degrees. We don’t even know what X is right now. Anyways, if you find anything out please do let us know!
 

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Will do, but it may be difficult to pin down "x" without some input from the HVAC manufacturer. Chances are the answer will be some integral of the inside and outside temps, with the resulting "difference factor" determining the turn-on threshold. Keep in mind that these are likely the same programmers who brought us fuel DTE's that "wig out" if you add less than 5 gallons or fail to turn the car off while fueling. Sadly, needless complexity is something we're already used to.
 

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Discussion Starter #14
Will do, but it may be difficult to pin down "x" without some input from the HVAC manufacturer. Chances are the answer will be some integral of the inside and outside temps, with the resulting "difference factor" determining the turn-on threshold. Keep in mind that these are likely the same programmers who brought us fuel DTE's that "wig out" if you add less than 5 gallons or fail to turn the car off while fueling. Sadly, needless complexity is something we're already used to.
Maybe Nissan decided to omit it from the manual on purpose to save us the headache :LOL:

In any case, I’ll be following this thread for potential updates...
 

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Update: Along with my F1 instructor today, we actually managed to find a reference to this in the OM. It said simply, "the system may turn on the heated seats and wheel". That's it, no details whatsoever. However, one instructor said he recalls hearing 45 degrees as the "magic number" in one of his briefings or meetings, he just can't remember where he heard it. I made him promise to email or text me if he recalls the source. He said it's also likely they'll turn on regardless of whether they were "last on" when the car was shut down, because the HVAC runs under a wholly separate firmware algorithm during RES than in normal operation. You might want to try confirming that. The existence of a "magic number" would also imply that it's a simple ambient temp measurement and not an integral, so you might want to try it some morning when the car's outside temp reads 44 and then later when the thermometer rises a bit.
 

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Discussion Starter #16
Update: Along with my F1 instructor today, we actually managed to find a reference to this in the OM. It said simply, "the system may turn on the heated seats and wheel". That's it, no details whatsoever. However, one instructor said he recalls hearing 45 degrees as the "magic number" in one of his briefings or meetings, he just can't remember where he heard it. I made him promise to email or text me if he recalls the source. He said it's also likely they'll turn on regardless of whether they were "last on" when the car was shut down, because the HVAC runs under a wholly separate firmware algorithm during RES than in normal operation. You might want to try confirming that. The existence of a "magic number" would also imply that it's a simple ambient temp measurement and not an integral, so you might want to try it some morning when the car's outside temp reads 44 and then later when the thermometer rises a bit.
Thanks for the update! I'll definitely be paying attention to this the next time the temperature reaches those levels in my area. It'd be nice to have a little more control on when it turns on, but this would certainly be better than nothing!
 

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It'd be nice to have a little more control on when it turns on, but this would certainly be better than nothing!
Keep in mind that if the seats were "last off" when you shut it down, they'll turn off again when you get in the car and cancel RES. The HVAC only runs its own show during RES warmup. You don't have any control over the temp from the heater and AC during RES either, the system automatically aims for 75 degrees. Once you cancel, if your "last" settings aren't appropriate for conditions, you'll still need to change them yourself. Unless I need defrost, I always leave the system in our '13 on Auto so I have to do minimal fiddling.
 
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