PFMEA severity with no knowledge of operating conditions

[JonnyB]

Hi all, I think I am going mad.
I am currently producing a number of PFMEAs for a customer (low volume electrical assemblies for automotive). I have been in discussion with their SQE for a few days now over what failure effects I should be including and their severity scores.

The extent of the technical information we have been provided is a "drawing pack" consisting of a 21 page power-point presentation - There are 21 parts in the drawing pack.
The drawings contain no electrical requirements (except for a pin to pin diagram), no functional requirements and only a very brief description of their intended use in the title of the slide (e.g. RHS ECU - RHS Camera Cabin Cable).
To give an example of the lack of control over the build standards, the customer did not want to purchase the proper tooling for one of the contacts defined, so said that we could solder cable directly to the contact (no crimp form) - when I asked for a concession document to fill in and ultimately include with the PPAP, I was told we didn't need one because the fixing method was not defined on the drawing...

The SQE is arguing that I need to consider all failure effects from the end users point of view. Am i being obtuse when I argue that without any knowledge of the function, environment or operating conditions I cannot possibly know what the potential failure effect at the end user is?
I am trying to keep the PFMEA a useful document, in which case I am defining the scope as applicable to our companies processes and subsequent assembly steps. Is this still in line with AIAG? (I am considering end user but ultimately have determined there is not enough information to produce anything of value with any consistency).

 

[Ron Rompen]

Without knowing what the function/environment/operating conditions are, your failure effects will have to be pretty generic. For example, using the failure 'unsoldered connection', the failure effect would be 'Fail to Function'. That may not be COMPLETELY accurate (depending on the design) but it should be sufficient for the SQE's purpose.
If he/she disagrees, then it would seem reasonable (to me) that he/she TELLS you what the failure effects would be of various failure modes.

As for the concession document, I agree with you completely in your request for one. Make sure you note it CLEARLY on your PPAP submission (should be captured in the Process Flow, PFMEA, Control Plan) that this is a non-standard process, being used per customer instruction. CYA as much as you can, because if it comes back at some point, it will be YOU that gets blamed for it.

 

[John C. Abnet]

Good day @JonnyB ;
I (am sure others) feel your pain.

You and your team are taking the correct approach by TRYING to determine the effects as far down stream as possible. If it helps, remember that AIAG 4th edition (same applies to AIAG/VGA harmonized), defines customer as "...SHOULD normally be end user, BUT.... Customer ...could be the next operation,... locations, etc...".

Your organization is at the mercy of the customer in regard to how far downstream the effects are known. (Consider the commodity supplier, wherein, a product [e.g. bolt], may have MULTIPLE applications across multiple platforms. In those cases it's even more difficult for the customer to "know" (identify), the various potential effects.

@Ron Rompen provided you with wise counsel in regard to ...
"...your failure effects will have to be pretty generic. For example, using the failure 'unsoldered connection', the failure effect would be 'Fail to Function'. That may not be COMPLETELY accurate (depending on the design) but it should be sufficient for the SQE's purpose. ...

BTW:
The original post mentions "...producing PFMEA for a customer". I'm hoping that your organization is more selfish than that and is indeed developing PFMEA for your organization and NOT simply because the customer asks for it. That approach alone may help/change your impression of not knowing the customer and/or end user potential effects. PFMEA can/should be a great resource and a living tool within your organization.

Hope this helps.

Be well.

 

[JonnyB]

I have managed to convince the customer that maintaining the scope of the PFMEA to the realization of product manufacture, I can produce a useful document that can be controlled and maintained considerably easier.
Thank you both for your responses!

@John C. Abnet - I have been slowly brining individuals within the company around to the use of PFMEAs for our own benefit, whereas before they have merely been a tick in the box exercise and rarely addressed any actual risks. The one useful thing to come out of this customers approach is that it has stressed the importance of the work I have been trying to encourage since I started 6 months ago.