2nd Gen Non-Engine/Transmission just change batteries (question)

[RCrosby]

hey guys, a few days ago I change the batteries for the first time, question is under the driver side batt. there was a round button, with two wires under it, what is this switch for, I just never seen one before. thanks

 

[bmoeller]

It is a temp sensor for the batteries. The PCM uses it to adjust the voltage output of the alternator.

 

[Woodenhead]

You'll notice when it's super cold out your voltage will read a little higher. That's the computer sensing the battery temp and bumping the voltage to help out with the cold.



Mike

 

[DieselDoghouse]

Cold lead-acid batteries do not like to charge as well, hence the entire charge-contour built into the PCM software.

 

[WestTN]

For a little more specific answer, it is the AIT, Ambient air Temperature sensor.