The journey of reviving my '07 DB9 is (I hope) almost complete. The engine is back together, wiring connected, and I'm ready to turn it over. Naturally I expected faults, but I'm getting the "check battery off switch" message. After some google-fu I've learned the trick is to press the battery reset button located either under the rear passenger seat or in the rear passenger footwell. After checking these spots, pretty much everywhere else, and eventually pulling out the interior to trace the wiring, I can find no such button in my car.

I've read alternate solutions of disconnecting the battery for an hour, or locking and unlocking the car several times in order to achieve the desired result, but neither of these have worked for me.

Any chance someone here can provide some advice or other potential solutions?

 

I *think* that putting the key in the ignition or turning on the ignition should reset the switch state, but not sure.

 

Yes, that does reconnect the battery disconnect switch in the trunk. My car has that switch and I can hear it activate when I press it and deactivate when I put the key in the ignition. From my research it seems this message refers to a different switch which is located under the rear passenger seat or in the rear passenger footwell. Pressing it resets certain systems in the car. My car does not have a switch in either of these places.

 

It is underneath the seat. Pull the rear seat up (the one that covers the battery), and it should be on the side of the battery. I wish I had taken a picture when I did the battery in my 2007. It was a PIA - heavy battery and trying to lift it into place.

 

Thanks for the response, but it's not in that location. I have the entire rear interior pulled out and there is no battery reset switch.

 

Then there is no switch. I think that on 2007 and onwards the switch was removed and replaced with auto-reset with key in ignition. I know my 07 vantage does not have one.

I do also know that the switch state is checked by the CEM unit, and there is quite a bit involved with it. I went over the electrical system in my car and disconnected CEM, disconnected CAN bus, disconnected front fuse box etc. can resault in this message being displayed. But considering that you hear the switch reset, I think it's safe to say that the CEM is doing it's job.

Is there anything else in the car that could be the issue?
Is everything connected? Have you double-checked all connections?

 

I'm fresh off an engine rebuild, so lots was disconnected. I'm working my way through it all now including several other faults, so it may just go away as I resolve other issues, but that's nice to get more info about the switch being removed and being auto reset. Thank you.