2nd Gen Non-Engine/Transmission Battery Tray Question

[drag racer]

Factory batteries finally gave up after 3. 5 years. Putting in a new set of Optimas today, and noticed on the bottom of the driver's side battery tray, there is a spring loaded circular disc (about the size of silver dollar) with a wire going to it underneath the tray. When the battery sits down on it, it pushes it back down and looks like it makes some kind of circuit. Anybody know what this is, or what it does? I would look it up, but I'd rather get back out in the shop.

 

[tarussell]

Somebody asked about that thing around a month ago and it is supposed to be a battery temp sensor for the ECM . Thomas

 

[kluther]

it is a temp sensor. it for charging rates. raises voltage when cold

ken

 

[drag racer]

I'll be darned. Thanks guys for the info.