It appears that both my rear tail light clusters are not working. The reversing lights do not work. When I use the positional indicators I get a fast rapid display on the instrument panel. The warning light display state both stop and indicator lights failure. The rear fogs and high level lights, headlights, front and front wing indicators still work. Occasionally if I twiddle the indicator bulb briefly it sometimes lights up for a second. I have changed the bulbs and also i believe the relevant fuses brake light F37 and reverse light F31. I have noticed the connecters seem to be in poor condition. I have attached a picture of the worst (drivers side). I have now used contact cleaner but problem persists.

I have recently installed a new battery. Following a non starting failure and RAC informed wrong battery (underpowered) originally fitted. The only other issue which could be coincidental is that the rear parking sensors have worked intermittently since purchase but lately now sound on start up every time and will I sometimes need to restart car for beeping sound to disappear. Any ideas as to my next step please?

I had a similar issue with my connector, with the end pin going bad. I cut the connector down and used a spade-socket crimp connector to make my own connection for the burned one. I still get RIGHT REAR FOG LAMP error though, but it may be a CANBUS issue caused by a non-CANBUS LED bulb, but I haven't checked it out yet.

Thanks Mytheroo. Just to update I started by cleaning the contacts this time with white vinegar and salt (2:1). Offside as per picture definitely worse than the nearside. I then also cleaned the lens cluster contacts also even though they appeared fairly clean. I notice that for the contacts that attached to the lens contacts had quite wide gaps between some. With the help of a fine micro screwdriver i managed to close the gaps with damaging or losing any of the contacts. I finished of by spraying all the contacts with WD40 contact cleaner.

Both rear lights are now working fine. Surprisingly there was no fuse or relay involvement with this problem. My parking sensor issue has also resolved. Therefore I conclude that I had not cleaned the contacts sufficiently originally and ensuring that the gap between the contacts that feed to the lens is at a minimum was key to resolving the issue.

I found this stuff really good at cleaning and protecting contacts.
https://www.jaycar.com.au/deoxit-contact-cleaner-rejuvenator-solution-kit/p/NS1436