International LT 2020 Sleeper AC shuts off when volts get low, autostart does not kick in.

Discussion in 'International Forum' started by shakin, Sep 4, 2020.

  1. shakin

    shakin Bobtail Member

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    I brought it in 3 days after the one year warrantee had expired because the AC would shut off in the sleeper instead of the autostart kicking in and 4 of the high dollar batteries were shot, replaced all batteries this was like a month ago, AC auto start function worked together again now it's doing the same thing, AC just shuts off, autostart does not engage. I have the electric apu system. Anyone else figure this out?
     
  2. Heavyd

    Heavyd Road Train Member

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    I replied to your other post, but I'll add some more here. You still need to plug into it to see what the body controller is reading for cab temp. It the temp sensor in the cab might be faulty and reading cold all the time so body controller thinks its cold enough and therefore never initiates the system to run. For the system to run, you need the park brake set, hood closed, no vehicle speed and must be in neutral. If any of these safety interlocks are showing error it will not start. You need to a computer plugged in to see all these.
     
  3. shakin

    shakin Bobtail Member

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  4. shakin

    shakin Bobtail Member

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    Hey thanks so much. I brought it in they replaced the air temp sensor and raised the auto start setting to 12.4, I told them 12.3 and it still turns on way too much. Now it's doing it again this time I'm plugged into shore power, thinking garbage sensor again. Killing me. I'll have to bring it in for a third time. Thanks for your response!
     
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  5. Cooltrucker09

    Cooltrucker09 Bobtail Member

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  6. Cooltrucker09

    Cooltrucker09 Bobtail Member

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    So what was the problem that caused this issue? I am in a 2019 prostar lt electric apu and the ac shuts down like the low voltage sensor shuts off like a breaker being tripped after running for 11-13hrs But the auto start does not start the truck and I still have power to all power outlets and lights, refrigerator, cb. The power for the hvac system will kick back on like a breaker resetting after about 10- 20 seconds. Auto start will not start truck for a least another 2-3 hours and if I leave hvac off it will turn on again for a few minutes.. what did you digure out that was the main cause??
     
  7. 4wayflashers

    4wayflashers Road Train Member

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    It sounds like my truck is doing the same thing. The auto start works as it’s supposed to. My issue is the bunk AC shuts off before the voltage drops low enough for the auto start to start the truck. The AC will work just fine until it just shuts off when voltage drops to 12.5
     
  8. Hankcantkook

    Hankcantkook Bobtail Member

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    U ever fix this issue?
     
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  9. 4wayflashers

    4wayflashers Road Train Member

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    Nope. I have noticed that it works like it’s supposed to when the temps are around 80 or lower and it’s dark out. Any higher temps then that and it just shuts off at 12.6.
     
  10. Heavyd

    Heavyd Road Train Member

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    The module that controls the no-idle cooling may be seeing low voltage to cut it out while the body controller is seeing good voltage to prevent an auto start event. The no-idle cooling module and body controller module are two separate components in different locations with different battery feeds. Even with newer and good batteries, it is possible to have a bad power supply wire to the controller for it think the batteries are too low for proper operation.
     
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