2013 Aurion Heater Control Unit Issue?

[Charles Frederick Augustus Millions]

Hi!  I'm hoping someone here can help me.

I've got a 2013 Aurion and a few months ago the heater control unit stopped responding. The light goes on, but none of the controls work except the hazard lights button. All fuses/relays are in good order.

I bought a 2nd hand replacement heater control unit and fitted it and it worked for a few weeks but now it's doing the same thing again :(  I have exactly the same problem! Has anyone faced this or do you know how to fix it?

I made a short video of the issue: https://youtu.be/PWW17AuocuM

Thanks in advance.

[Tony Prodigy]

Man, this is something that can drive me nuts.

I suspect that you are not getting contact on certain pins on the molex plugs. If the new one worked for a few weeks then suddenly did the "same thing",

I would hazard a guess that one or more pin outs may have made brief contact, enabling the unit to function temporarily, and during the course of driving it may have separated again.

It can't be a co incidence that both controllers have failed in this same way.

If you have a multi meter, I'd check continuity across all the pins in the molex to see if you have a break. 

With the car off, Set the meter to resistance/continuity and probe both ends of the plug/s

Alternatively, you can power up the vehicle and set the meter to DC Volts and look for voltage across pins. I'm not sure what voltage you will get as I don't have a schematic.

Maybe someone can provide a schematic on this.

Hope this helps. It's hard trouble shooting remotely. You just have to try and rule out the simple things first.

Let us know what you find.

[trentmeyer23]

Molex connectors are used in PCs, not cars.

There is possibility that there may be a short circuit in some of the wiring for the unit. I would have it diagnosed by a decent auto electrician. 

A wiring diagram could be obtained through a Haynes/Gregorys manual.

[Tony Prodigy]

1 hour ago, trentmeyer23 said:

Molex connectors are used in PCs, not cars.

There is possibility that there may be a short circuit in some of the wiring for the unit. I would have it diagnosed by a decent auto electrician. 

A wiring diagram could be obtained through a Haynes/Gregorys manual.

Ok Trent. Not molex then. Pin sockets.

If there was a short then a fuse would have blown no ?

[trentmeyer23]

In my experience, a short to ground will likely blow a fuse(not always). An internal short usually won't blow a fuse, but can cause issues.

Regardless, it is important to rule out any issues with the inputs/output on the unit.

[Tony Prodigy]

2 hours ago, trentmeyer23 said:

In my experience, a short to ground will likely blow a fuse(not always). An internal short usually won't blow a fuse, but can cause issues.

Regardless, it is important to rule out any issues with the inputs/output on the unit.

Yes. That's what I was trying to say.