Dirk

Hi, think I will remove and see if I can see any faults and clean the contacts, you never know. definitely not going to pay that.

Hi all thanks for the help, I agree it looks like switch is the way to go next although just had a quick search and design 911 want £400+ for the switch!

Hi it’s reading around 12.5 volts when off and then goes to 14.5 when running. Had a look at the cable but it comes up through the windscreen air vents so bigger job then I thought likely get to it via taking the pcm out which I’d rather not do. Took a video off what is happening and will see if I can upload it.

Thanks, will get hold of a multimeter next week and see what I get, the battery was a decent make (Bosch) and only 1.5 year old was just wondering if people on here who have had battery/ alternator issues also had this happen.?

Hi Boxer boy thanks for your help, it’s running at around 13v before starting, and then no problem when driving so assuming the alternator is charging the battery, it always starts it just robs power to the instrument cluster at ignition which resets the clock and fuel gauge. 
The previous owner has spliced a cable into the electrics for a sat nav/dash cam which I am going to remove at some point was wondering if its shorting at ignition?

Thanks BBB, can I ask when you start the car do you turn the key as far as it will go? 

Hi, I am posting on this thread as I feel it is likely related. (Battery) My 987.1 can reset the clock and fuel gauge on start up, can cause issues where I fill up at the petrol station on low, get back in start the engine and the display goes blank then reverts to the previous fuel level, which results in the car telling me that it is empty when I know it is at least half full.

I changed the battery last year with mixed results, and I am keeping it on the trickle charger, could it be the ignition, I can start the car by turning the ignition 1/2, 3/4 or all the way? Is this normal? Or is the cluster a usual fail point?

Cannot see any other threads with this issue.