Indicators and brake lights working together!!

Hi I'm DJ from Belfast I have a 1996 Defender Hardtop, I'll get some photographs up when I work out the technology. I'm having a problem with the electrics, not unusual given the age of the Landy, when the brakes are applied the indicator dash light comes on. When the the indicators are used the brake light and indicator on the drivers side are coming on together. When the hazard warning lights are used the indicators and brake lights are coming on together. I suspect this is an earthing problem, any suggestions as to how to get to the source of this problem would be very welcome. Thanks

Where the rear wireing loon goes into the chassis check there not corroded and damaged, mine did similar and it was there the problem

Thanks I'll have a look at that and see what happens

And water/corrosion in the lamps themselves