Car sometimes dies completely when powering off then turns back on
#1
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Hello fellow CT owners!!!
2014 CT200H F-Sport 58k miles
Lately when powering off the vehicle, the car sometimes cuts off completely as if the battery is completely dead or was disconnected. Nothing works, the brake lights, radio, etc... Any where from about 30 seconds the car will automatically just turn back on into acc mode with the clock being reset and my AC Settings. The other day while powering off the car and the car cut off for about an hour before going into acc mode. However, this time, I was unable to control any of the windows from the drivers side except for the driver window.
Besides this, the car runs flawlessly, the 12v battery in the trunk is newer so I know it is fine. I've checked the cables and nothing seems loose. Any advise on what is causing this? I really don't want to have to replace the entire infotainment system.
Tomorrow I'll unattach then reattach the battery terminals in the trunk to see if that does anything. I did see someone ask same question in a different forum so I know I'm not the only one that's had this issue but the other forum is older and didn't have an answer.
Any help or info much appreciated!
2014 CT200H F-Sport 58k miles
Lately when powering off the vehicle, the car sometimes cuts off completely as if the battery is completely dead or was disconnected. Nothing works, the brake lights, radio, etc... Any where from about 30 seconds the car will automatically just turn back on into acc mode with the clock being reset and my AC Settings. The other day while powering off the car and the car cut off for about an hour before going into acc mode. However, this time, I was unable to control any of the windows from the drivers side except for the driver window.
Besides this, the car runs flawlessly, the 12v battery in the trunk is newer so I know it is fine. I've checked the cables and nothing seems loose. Any advise on what is causing this? I really don't want to have to replace the entire infotainment system.
Tomorrow I'll unattach then reattach the battery terminals in the trunk to see if that does anything. I did see someone ask same question in a different forum so I know I'm not the only one that's had this issue but the other forum is older and didn't have an answer.
Any help or info much appreciated!
Last edited by stocktrader240; 08-21-24 at 11:42 PM. Reason: Misspelling
#2
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
Hello fellow CT owners!!!
2014 CT200H F-Sport 58k miles
Lately when powering off the vehicle, the car sometimes cuts off completely as if the battery is completely dead or was disconnected. Nothing works, the brake lights, radio, etc... Any where from about 30 seconds the car will automatically just turn back on into acc mode with the clock being reset and my AC Settings. The other day while powering off the car and the car cut off for about an hour before going into acc mode. However, this time, I was unable to control any of the windows from the drivers side except for the driver window.
Besides this, the car runs flawlessly, the 12v battery in the trunk is newer so I know it is fine. I've checked the cables and nothing seems loose. Any advise on what is causing this? I really don't want to have to replace the entire infotainment system.
Tomorrow I'll unattach then reattach the battery terminals in the trunk to see if that does anything. I did see someone ask same question in a different forum so I know I'm not the only one that's had this issue but the other forum is older and didn't have an answer.
Any help or info much appreciated!
2014 CT200H F-Sport 58k miles
Lately when powering off the vehicle, the car sometimes cuts off completely as if the battery is completely dead or was disconnected. Nothing works, the brake lights, radio, etc... Any where from about 30 seconds the car will automatically just turn back on into acc mode with the clock being reset and my AC Settings. The other day while powering off the car and the car cut off for about an hour before going into acc mode. However, this time, I was unable to control any of the windows from the drivers side except for the driver window.
Besides this, the car runs flawlessly, the 12v battery in the trunk is newer so I know it is fine. I've checked the cables and nothing seems loose. Any advise on what is causing this? I really don't want to have to replace the entire infotainment system.
Tomorrow I'll unattach then reattach the battery terminals in the trunk to see if that does anything. I did see someone ask same question in a different forum so I know I'm not the only one that's had this issue but the other forum is older and didn't have an answer.
Any help or info much appreciated!
Well, never assume that just because a battery is newer, that it isn't slowly failing. Step 1 would be to have it load tested and/or watch the 12V bus with a meter to confirm that you aren't getting substantial voltage drops during these times. There could be a bad plate-plate connection within the battery, which may sometimes give you 12+ volts, but could collapse when you try to demand load from it. Keep in mind that when the car is running, the DCDC is supplementing the 12V system from the HV battery, so when the DCDC turns off, it's all on the 12V batt. This type of failure mode can be a red herring, because with no load being demanded, the batt may very well read ok.
Cheap, easy thing to check first before fretting too much.
#3
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Well, never assume that just because a battery is newer, that it isn't slowly failing. Step 1 would be to have it load tested and/or watch the 12V bus with a meter to confirm that you aren't getting substantial voltage drops during these times. There could be a bad plate-plate connection within the battery, which may sometimes give you 12+ volts, but could collapse when you try to demand load from it. Keep in mind that when the car is running, the DCDC is supplementing the 12V system from the HV battery, so when the DCDC turns off, it's all on the 12V batt. This type of failure mode can be a red herring, because with no load being demanded, the batt may very well read ok.
Cheap, easy thing to check first before fretting too much.
Cheap, easy thing to check first before fretting too much.
#4
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If you have an independent hybrid shop nearby that may be a better choice than a dealer. Beware of the dealer overselling several more unrelated repairs in addition to what you brought it in for them to diagnose.
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andg404
CT 200h Model (2011-2017)
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03-24-18 03:21 AM