TCH battery fan - when should it run?
 

I've been wondering if the problems I've been having with my hybrid's battery (3 modules replaced so far) have something to do with the fan. Should the fan run all the time that the car is in charging mode (going by the dash/radio display), or only when the cells start heating up? Since I've never known when it (the fan) was running I can't tell if/when it is. I just tried starting the car, left it in park and cranked the heat up, this caused the engine to start and the display to indicate charge. However, when I checked from the trunk, the fan isn't running.

Thoughts?

Re: TCH battery fan - when should it run?
 

The fan is run at certain temperature thresholds. It is a PWM controlled 12V fan with 7 speeds, 0-6. It is frequently off (0) when the battery is under about 90°F. Speed is increased incrementally as each temperature threshold is hit.

It will be at speed 5 at 122°F and as it hits about 131°F, it will run full blast.

The fan sound isn't particularly detectable at speeds 1-4. Speed 5 can be heard if you are really paying attention. Speed 6 is very obvious.

The best way to be certain is to feel for the exhaust at the exit duct.

The only way the car can generate cabin heat is like any other car - pass hot coolant through the heater core. That's why the ICE ran - you needed the ICE to heat the coolant to heat the cabin.

You don't seem to understand that you are 3 modules into a many-module game of whack-a-mole that likely has nothing to do with your fan. When your battery pack failed, you need to think of it as a 34 wheeled car with 34 bald tires. One of those tires blew, and you replaced it with a presumably better not-so-bald tire, but you left 33 bald tires on it. Which one will fail next?

I recently posted my test results of a 2007 Camry battery with module capacity AND full reconditioning. For a reliable repair, 14 modules needed replacement... AFTER they were reconditioned:

https://www.greenhybrid.com/forums/f...results-31216/

Unless you actually reconditioned the pack, you are dealing with is the horribly deteriorated BLUE lines on that chart with very low capacities.

Granted, if you're not in AZ, it's probably not this bad, but it's illustrative of the issues.

You likely replaced based on voltage. Note that in that pack NO modules failed. They would all hold voltage.

I would encourage you to read that post thoroughly from beginning to end (again). :)

Re: TCH battery fan - when should it run?
 

Yes, as you saw, I read the post, but you gave a vague response regarding reconditioning. I don't have the time to do a module-by-module reconditioning. Other than a grid charger, anything else I can do?

Re: TCH battery fan - when should it run?
 

That wasn't a vague response. That was me being unwilling to spoon feed you information at great time expense to myself. That information is everywhere.

You don't have time to recondition every module, but you have time to pull the pack maybe another half dozen times, break it down, replace a failed module and then put it all back together again? How long does that take you?

A grid charger is only half the solution. You need a discharger as well. Those can work very well assuming your pack is in reasonably good health and only suffering from voltage depression, but you can't be certain without module level testing. Heck, you don't even know that the modules you installed are any good. Clearly in the test case I posted, it absolutely wouldn't have worked.

Nothing else you can do except sell the car or scrap it.

Re: TCH battery fan - when should it run?
 

You can try this.
Does not mention TCH but who knows.... As it's not cooling, right?

Re: TCH battery fan - when should it run?
 

He's assuming it's not cooling, and one would presume that he's already cleaned it because he's had the pack out enough times to replace 3 modules.

Re: TCH battery fan - when should it run?
 

Yeah, presumptions are like assumptions. No telling until man says so.