[Just2fast5]

Hi all 

I was wondering if someone could help me here please. 

I have retrofitted neck warmers in my F33 but I cannot figure out this issue, its looking like the heater element is faulty but I just want to be 100% before I buy any more parts. 

I've checked all the wiring and it's fine I've checked the ISTA wiring diagram and it's 100% like for like I just can't see both heating elements being gone although I have brought the seats second hand with no back ground on them. 

The seats are from a M4 with the control modules they come with being used after I coded them to my car to remove all errors. I just don't know if there are any more cables the M4 seat might require that would not show up on the neck warmer diagram? Maybe a extra ground wire? 

I can get the fans to kick in with the ISTA test plan but cannot get them to heat up any help with where to look would be appreciated. 

Thanks 
Daniel

[user0086]

It's a simple PTC heating element, why don't you just measure the resistance of the heating element?

[Just2fast5]

It's a simple PTC heating element, why don't you just measure the resistance of the heating element?

I've never done anything like that before, how would I do that? Would that prove if the heating element needs replacing? 

Thanks in advance

[MOCKING_BIRD]

It's a simple PTC heating element, why don't you just measure the resistance of the heating element?

I've never done anything like that before, how would I do that? Would that prove if the heating element needs replacing? 

Thanks in advance

It's wirring problem. 
Ground

[Just2fast5]

Hi there 

Thanks for your reply, what makes you say it's the ground? Reason I ask is because I have checked these and they seem to be fine but is there anything else I need to check to make sure? 

Thanks 
Daniel 


It's wirring problem. 
Ground
[/quote]

[Spirit5676]

Just measure the resistance of the heater with a decent multimeter. This is simple just look at the wiring schematics on ista that you're already using. If there is open circuit (no resistance) the element need replacing or fixing.

[Just2fast5]

Hi there 

I finally got around to finding the time to check the resistance of the heater and here is a picture of what it was showing.

Is anyone able to tell me if this is correct or not please? 

Thanks 
Daniel 

Just measure the resistance of the heater with a decent multimeter. This is simple just look at the wiring schematics on ista that you're already using. If there is open circuit (no resistance) the element need replacing or fixing.

[Node]

Sounds about correct. DEFINITELY not a "line break"!

[Just2fast5]

Do you mean the resistance is correct? 

Sounds about correct. DEFINITELY not a "line break"!

[Node]

I don't know what exactly it should be, so I can't tell "correct". But sounds reasonable!

BMW description says warmers are 150W so at 14V resistance should be 14V*14V/150W = 1.3Ohm. Your values are near enough. Probably that multimeter would not show zero even if you short it's wires together.

---

Also when hot resistance will increase... So it's a BIT on a high side, but as I said - close enough. I'm pretty sure you have wires missing/broken.