I have a suspect failing HV battery in my just acquired ‘08. It’s my 4th gen2 purchased in last year and though the other 3 had 200-260k miles this 169k is first to cause concern with hybrid battery. Admitted I’ve learned little about Prius still and my confusion is why the battery cooling fan won’t turn on even after driving considerable time with the red triangle on? Fan is clean and works with direct current and fuse is good, but no power at its plug even with battery casing considerably hot to touch. Can a failing battery cause the fan not to turn on? I read there’s no fan relay but it’s triggering is internal with the battery ECU. Onboard diagnostics shows blue bars cycling between 2-7 bars with occasional 7 green. ICE seems to run fulltime, even parked or at stoplights. Any feedback is greatly appreciated, thanks.
best thing is to scan the codes with an auto maxi 200, or at least dr. prius. you can't rely on the cooling fan to come on when you think it should, you have to know the temperature parameters and watch the scanner. any corrosion on the fan plug?
I have an Autel ap200 that shows code POA84, cooling fan control circuit issue. Other code is is P3000. No corrosion on fan plug, but we found another plug.right rear near fan motor, with corrosion and a broken pin we initially thought was our taillight issue. Just replaced bulb and it works now with that bad plug. Friend is at u pull it now getting plug. Hopefully that’s the issue. Will update after replacing plug.