battery disconnect fix

[clummus]

sleddog I sent you a PM..

[JATR4]

If what we are doing is erasing the KAM (Keep-Alive Memory), isn't that done by just disconnecting the 12-volt battery for 5 minutes? That is how it was done on the Honda Civic Hybrid.

 

Found this in a 2012 Fusion/MKZ Hybrid Modifiers Guide:

 

"Keep-Alive Memory (KAM) Power

 

The electronic engine and/or transmission control modules and the HVTB BECM require low
battery voltage (12 volts) to be supplied at all times to maintain the keep-alive memory (KAM).
Keep this in mind when installing load disconnect switches or solenoids."

 

Any ideas?

Edited September 11, 2013 by JATR4

[acdii]

The systems are so integrated, who knows. Technically, when the key is off, the HVB relays are disconnected, so the power from the pack should be totally isolated, but are they totally or is there some power being sent via the DC-DC convertor to the computers?

 

Reason I say this, in a crash the relays are supposed to disconnect the HVB, same as a fuel pump cutoff. If so, why a battery disconnect plug? Redundancy, or is there a live connection to something?

[Fastronaut]

Turn the car off.

Fold down the rear seat backs, open the access panel, and pull the HVB disconnect.

Disconnect the negative terminal of the 12 volt battery.

Do NOT close the car doors or the trunk.

Wait long enough for all stored charge in the car to drain away, (5 minutes, 10 minutes, 15 minutes???)

Reconnect the negative terminal of the 12 volt battery.

Reconnect the HVB.

After I got the PCM update, my Fusion "forgot" where home was located for EV+ mode. Does that mean I had Keep Alive Memory reset by the dealer when the update was done?

[B25Nut]

You lose the EV+ memory whenever you get an update or reset your mileage. It usually takes less than a week to relearn your locations.