Battery overheating and Battery fan on full

If problems exist in inverter cooling. This is a thing. But would be hard pressed to be a thing when the car is first started in the morning it would at least take a couple minutes for the battery to get up to temperature. So maybe there's some problems with the sensor Arrangements inside of the battery? possibly.

 

Your battery is cold in the morning, not hot... The reason the fan is on is not because of the heat, but because that's the default setting when you have a problem with your hybrid system and it's been shut down. If you disconnect your 12v battery those codes will be cleared from the system and car will run normally.

But more to the point, get one of these OBD2 readers: Panlong OBD2 Scanner Bluetooth OBDII Diagnostic Tool Car Code Reader Turn Off... | eBay and use Dr. Prius app on your phone to monitor hybrid battery health and temperature. Of course if you really do have a cell that's running hot, the fastest way to find it is to pull the cover of the pack off after driving for a while and point a thermal camera at it and the hot cell that needs to be replaced will be very easy to locate.

 

Hello and welcome to PriusChat!

What warning lights are coming on the dashboard? What was happening before you had the hybrid battery "fixed"?

Do you know what trouble codes were stored before (with the battery repair) or what codes are present now?

As mentioned, having the battery fan turn on high speed usually happens when there is a fault with the hybrid battery.

Having codes and data from the battery ecu would be helpful. Here is a thread that reviews several scantool devices and apps.

Dr Prius with a "generic" bluetooth OBD2 adapter is handy for monitoring battery voltage (but it is not reliable to view codes).

Something like the Autel AP200 can scan codes, data, and more for all systems (but is less useful than Dr Prius for battery data).

https://priuschat.com/index.php?posts/3290690

Posted via the PriusChat mobile app.