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Thought I may share a recent experience.

I was asked recently via another forum about a code that I had not had much experience off P0AA6 & with techstream i found sub codes 526 & 612 I think from memory - I was aware they were to do with an HV (High Voltage) Isolation Error (to explain:- the HV electrical system is isolated or if you like - mechanically & electrically separated from the normal 12v electrical system & the body of the car for obvious safety reasons - this is why all HV cabling is orange too, to clearly identify the hazard )

From experience & a bit of lateral thinking & in the absence of any other possibilities like the car had been recently worked on or something my thoughts were "Water" 

Yes you heard me right Water:- I have personally witnessed & repaired hundreds of electrical nasties caused by water. Given that Doris had not long passed this sparked (excuse the pun) my attention.

Anyway to cut a long story short (well 1& half hrs) I located a spot underneath the car that looked "grazed" it was conspicuous because it was very clearly orange plastic when everything else around was covered in road muck, further chatting revealed that "its been doing it (throwing CHECK HYBRID SYSTEM) for a few days now but I just clear it down with my scanner mate & it seem ok after that its weird" - "oh yeah & it don't seem to happen when its just sat in park!"

mmmmmm I say scratching me chin - thats because that section is not energised until its in drive or reverse - anyway a quick clean with wd40 then a wash with solvent reveals a black tracking mark where HV electricity has been leaking (or tracking in the trade) to the chassis causing the CHECK HYBRID SYSTEM error, a bit of scraping some hot melt glue, wd40 & a bit of orange flexible conduit i had lying around, a spread of hot soldering iron & bingo Job done - no problem even after a good direct blast with hose pipe (don't do that at home folks!)

The chap was about to buy a whole new gearbox!!!!

So don't automatically assume the worst


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Well deduced and well found Richard 👍

I bet the chappy was happy that he didn't need to shell out for a gearbox.

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