Dreaded Drivetrain Fault 2019 120aH BEV (not REX)

[g0rsq]

After 2 months ownership I have got the dreaded Drivetrain Fault message.
On dash it says HV fault, but is OK to drive, but to get it looked at before further damage occurs.

On ISTA i get four messages (after clearing all codes), three that are recorded:-

22280F, 21F0E4, 21F0E3

and one permanent fault 030F02

All four say "High-Voltage electrical system: insulation resistance below fault, or warning threshold.

I ran the test-plan for the active code and got a reading of 266 kOhm.

Continuing the test it appears the fault is NOT in the battery, but I can not diagnose further.

So my presumption is the fault is either in the cable or the EME.

I understand the cable can give issues (this is a 2019 car so probably not one of the faulty parts) but is there any way to further diagnose before replacing it, or what would anyone recommend before this, or taking it to a specialist? Maybe I can disconnect cable both ends and use a Megga meter to check earth leakage.

Car should have a newish 12V battery (told by previous owner) and it registered 14.8V in ISTA, but seemed to still be charging at 8 amps.

Car still drives and charges (AC) without issues.

 

[alohart]

Have you been driving on wet roads lately? If so, maybe water intruded into a HV connector. If the fault goes away after several dry days, maybe you have a clue to examine HV cable connectors (unfortunately, there seem to be many).

 

[g0rsq]

Have you been driving on wet roads lately? If so, maybe water intruded into a HV connector. If the fault goes away after several dry days, maybe you have a clue to examine HV cable connectors (unfortunately, there seem to be many).

I have been driving it on wet roads since I bought it!!!!

When I picked it up, a lot of roads were flooded (3 to 4 inches max) and I do not think it has stopped raining since....

I am hoping it is just dampness, but even if it is, there must be a problem, as it is not normal.

Today the fault actually cleared, for about 15 mins, but returned near end of journey.

I guess I need to get under the car and check the main cables going to the battery. This cable is only £200 new so may be worth replacing as a first step. I think this is the only cable with exposed connections, but moisture could be in the form of condensation, especially as very little heat generated when running.