Nissan Patrol 4x4 (Africa)

I was on-site on a project in Postmasberg and forgot the remote on the dash for the whole day where the Northern Cape sun completely trashed it. I arrived back at the truck to find the remote swollen and warped. Strangely enough, it still worked for a few months afterwards. But it no longer charged from either USB or solar and eventually died. I've not thought about it much and not used it for a few years...

Last week, I received a nice shipment of electronic goodies for some of the projects I am always busy with. And whilst putting them away and sorting out my electriconic component storage stuff, I came across the remote. I decided to butcher it.

Gathered the USB connection had broken off the circuit board, and the small PV panel attached to it so that one can charge from solar no longer works... And then the case looks absolutely horrible. Warped and broken. The face-plate for the remote was still in good nick though, so I removed it...

The following photograph is the front cover after removing the face plate. You can see it's not lekker...
Rummaging through my electronic components I hauled out a Lithium 1865 battery and an associated USB-C charge controller / battery protector.

I soldered the battery's + and - to the relevant points on the charge controller. I then desoldered the PV panel and the old battery from the remote control and soldered the output from the charge controller back to the remote's battery input. Voila. It looks like this in the case I printed (more on that in a bit).
I then knocked together a 3D design for a similar case - including space for the larger battery. The case did not come out perfectly on the front. I had to use build plate support for the 0.4mm depression for the remote's original face plate. This did not work fantastically and I had to resort to the dremel to remove some of it. No worries though, it will be hidden by the original face plate in any case.
Finally, I stuck on the original face plate, fired up my fridge and remote and tested. Works a charm. Clarification on the weird readings - I only run my fridge in the boot of the car when I use it so it has been off for a couple of days - hence the very high temperature (27 degrees). Also, the moment I plugged the fridge in to test the remote, the compressor started. Hence the 11.6V. The battery is good.
I've still got to design and print a back cover for the "new remote". But everything works again. It was a lekker simple project yesterday.