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Discussion Starter · #1 ·
Hi all
I have new fault that never seen before, im certain its related to batt sensor under battery tray and most likely a result of recent engine-mount change.
before I start digging and disassemblying, can you please confirm if issue with sensor can be caousing low voltage charge?
I noticed now I have 13.5V when running and no electrical components on, and dropping to 13.1V on heavy load. I could swear I used to have way over 14V when checking before, would 14.5V be correct?
  • would faulty sensor cause this? my reasoning is if system cant correctly detect battery temp, it would put minimum charge to not overload/overheat battery?
  • batt temp is still reported as you can see but not sure its actually 55deg C, seem way too hot for mild 20C day and engine barely started. Dead sensor or just cabling issue (maybe connector loose) ?
anybody had experience with such before?

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I have that error too in my car. Got it after i installed more batteries in the trunk (bass nerd)...
I´ll try to remember checking my charging voltage later today, see if that is a common thing.
 

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Discussion Starter · #4 ·
In the signal description for CEM-4F30, 55° C is default for a faulty sensor or open circuit.
so its highly possible sensor is simply not conencted aswell?
 

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13.25 volts is what mine is charging, idling.
Alternator is less than 2 years old, so o have never bothered to measure the charge as it was a new one.
But now i have to fix it too 😁

My Vida laptop was dead, so i´ll look at my exact error code tomorrow. I just remember it was something with the temps.
It might be as you guessed, that the charge goes down if the battery is hot.
 

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Discussion Starter · #7 ·
13.25 volts is what mine is charging, idling.
Alternator is less than 2 years old, so o have never bothered to measure the charge as it was a new one.
But now i have to fix it too 😁

My Vida laptop was dead, so i´ll look at my exact error code tomorrow. I just remember it was something with the temps.
It might be as you guessed, that the charge goes down if the battery is hot.
Im hoping thats the car logic, similar to cell phone battery sensor. Ill try to check mine this wwekend, hoping its jut disconnected after battery tray was removed.
Whats the correct charge on idle I should see, am I remembering correctly 14.5V ?
 

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Discussion Starter · #10 ·
Just to wrap it up - I can confirm the issue was caused by not connected sensor. Once I sorted it out, charging is back to 14.5V and no more errors. Would have never thought to troubleshoot charging issue there so +1 to knowledge skills, thx all for feedback.
 
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