I have a positive earth Daimler V8. I have tried to run my portable sat nav system using the cigar lighter. No joy. I understand that this is likely to be because the device needs negative earth. Has anyone overcome this problem in a neat and tidy way? I have seen a system that takes a lead from the cigar lighter into a second one with the feed wires reversed - but it was not pretty!

 

12V 24V Male Din Car Cigarette Lighter Plug Connector Continental Adaptor UK | eBay

you could just get one of these and a spare lead, and wire it yourself really easy and will look like a regular lead.

You could wire diodes internally and make it so it would work for both positive and negative earth by using them as a bridge rectifier, but there will be a voltage drop, but this may not be a problem as car electrics tend to vary quite a lot anyway, this would also be no use for a high current device, but should be fine for a sat nav so 1 adapter for positive or negative earth applications and no getting confused which one is which.

 

What I did on my Jaguar 3.8s is replace the stock rearview mirror with this Smart Mirror 2 escort Smart Mirror 2 Escort SmartMirror 2


It looks very clean in the car. It provides a rearview mirror and on the right side it functions as both a navigation system and back up camera display.

 

Primaz,
How does it get its power? Is there a cord hanging down from the mirror?
Lin

 

It is reasonably straightforward to convert to negative earth. When I rebuilt my Mark 2 in the 80s, my friend, who was an auto electrician did it for me. As I recall, it was as simple as stroking the bare end of a wire onto some contact on the car, but it is too long to remember.

 

Lin,


We tucked the cable in the headliner and you do not even notice it at all as it is hardly visible. The mirror setup to me looks very clean and unless you are know what the stock mirror looks like, nobody notices it not being the stock mirror. For me I like it much better as the mirror is a bit larger and provides a better view for driving. This gives navigation hidden so nobody even will see the navigation as well as it provides back up camera like a modern car yet also hidden from view.


To me many people put their cell phone, etc. off the cigarette plug and use some suction mount and those all look so tacky and ugly in my opinion. I think this is a good solution using the mirror/nav/camera setup. The other option would be to use a pop out DIN screen radio/nav unit. The problem of the Jaguar is that the location is a little too low and not ideal to see the screen but that would also be hidden when parked.

 

I have ordered the part recommended by TilleyJon since I do not wish to go away from positive earth.