Cold inside. Heater on blink

Latest update.

Removed heater,
Split it open,
Found that a transistor has popped. Clear burn marks and plastic cracked from the centre.
I am currently ordering new transistor from China.

Nissan spares quoted me 2 grand £ for new heater.
The transistor from China are $7.

Can anyone tell me if its able to drive with this heater disconnected???
I've drained fluids from the heater circuit but does that fluid act as cooler elsewhere?

On a 2012 there is a HV interlock built into all the connectors that plug into the HV juction box/DC Converter. [pack, motor, obc, heater, a/c] It is a long daisy chain and the signal thru it confirms that all the connectors are inserted.

i think you could disconnect it at the heater and leave it off, but inspect that connector to see if there are any tiny contacts in it that might be an interlock. 2013 is different, i can't find the wiring diagram to determine about the I/L.

I ran as normal. I made sure the ac was off because the pump is still connected and it will be without any fluid.

I ordered 8 new transistors - Auirg4ph505.
Hopefully just needs a straight swap.

I'm going to find someone who can IR test the heater elements.

I'm still awaiting the sensors from the breakers.

I feel like I might be getting somewhere. If I still can't get it fixed I'm going to sell it at a lose and get another car.

That's an N-channel insulated gate bipolar transistor, IGBT, rated at 1200V and 81Amps. Infineon Tech.
https://www.infineon.com/dgdl/auirg4ph50s.pdf?fileId=5546d462533600a4015355ba31da1519

How many are inside the unit-- 4 or 6 maybe? or do you have a picture?

With it open you may be able to measure the PTC heater resistance with a voltmeter.

sounds like you are making good progress.

[edit] i noticed that IGBT is missing an internal body diode, wonder if there are diodes on the board to perform the freewheeling function when if is switched off with current flowing? That could easily blow such a device especially if there is inductance in the load.