What's this Bosch Relay on Negative Battery Terminal?

Me being curious with the whole battery reset process, wondered about the first time I did it, I didn't remove the entire clamp cluster, which left this relay still connected.

Got to thinking that maybe that's not a good idea so I've done the process again, this time with the entire negative cluster D/C'd.

But...what the heck is this electrical component. Can't find a reference or clue as to what it is. AC relay perhaps?

I KNOW one of you knows! ;-)



Sent from my iPhone using Tapatalk

This appears to be a MEMS battery monitor sensor. It basically tells the truck the state of the battery, it's not relay.

pjones said:

This appears to be a MEMS battery monitor sensor. It basically tells the truck the state of the battery, it's not relay.

Click to expand...

Wow. Cool. Ya da man...thank you!


Sent from my iPhone using Tapatalk

Yeah it monitors the current going in and out of the battery.

I'd assume Ford monitors it, but I'm not certain. On Audi's it'll monitor how much draw, how long, and at what time of day it occurred, and I'm sure the system is smart enough to know if the key was on, lights, parking lights... etc etc. with all of this information it can judge the health of the battery.