I have a 2006 Honda Civic Hybrid.
The IPU fan seems to be running at high speed all the time except when the car is shut off ( key is not turned to ignition or the engine is not running)
How can I diagnose this?
I read online somewhere that the voltage, current and temperature together are used control / determine the speed of the fan.
Is this correct?
Am I looking for relays, resistors, temperature sensor(s), voltage controller, current controller, pwm controller?
And where is/are it/they located?
I bought and installed a battery pack grid charger for the ima battery and it seems to be working well.
I am just trying to see if I can resolve this one issue with the fan always running at high speed all the time the engine is running or the key is turned to ignition.
In the past it never seems to do that.
It would only run when needed then shut off - at least it appeared that way to me.
Any help you can provide would be greatly appreciated.
Thank you in advance for your help.

 

Which grid charger?

Did this occur immediately after the grid charger install?

 

Maxx Volts.

It seems like this started after I used the charger, I believe the second time since I charged it for longer (about 12 hours).

I thought there was the slight smell of burning rubber, but I cannot be 100% sure.

 

Your IMA fan should not run continuously. Rather than attempt to jury rig some solution, you should investigate the cause. The cause could be temperature driven. The fan is regulated by a PWM signal and efforts to thwart normal function via resistors or other means is ill conceived.

If the grid charger is not properly driving the fan during charging, the battery WILL overheat. If this first occurred after a 12 hr charge, it's possible, the pack got so hot, the car commanded it to run full speed for an extended period. Normally, it is only temporary unless permanent damage has occurred where overheating occurs under normal use. However, this is always accompanied by a CEL/DTC.

I recommend you contact Maxx Volts immediately.

Additionally, by your "i charged it for longer (about 12 hours)" comment, you are not using your grid charger correctly.

Grid charging should only be done when necessary and for a sufficiently long time to ensure all cells are driven to 100% SoC. The Maxx Volts supply is very low output and a proper grid charge would take over 27 hours. 12 hours is not a "longer" period to use it. It is an insufficient duration.

Good luck,

Steve

 

Did you ever find a solution to this? Having the exact same issue.

 

I've got the same issue after trial to install a Maxx Volts Grid Charger.
But my charger never works as how many trials and watchung install videos.
I'm really sure the charger delivered voltage to the fan or especially to its sensor.
And now the sensor is fully damaged and the fan is running on maximum permanent.

Is there any idea where this sensor is located or how to check?

Or maybe it's easier and when I connected the grid charger to the fan wires (!) somethings connection is lost?

Would a new fan installation help, is the sensor control a part of the fan unit?

Thanks for help.

 

Had the same issue after installing a Max Bolts charger. It fried a few of the components in the battery management module.
Once I replaced it with a working one pulled from another vehicle, the fan running at 100% issue went away and it worked as it did prior to the balance charger install.

 

I tried to contact maxx volts but they won't get back to me about the fan running all the time it's plugged in