Intermittent electronics error fault, when cold. Engine runs fine.

[Breezy_Pete]

I wasjust hoping you might find something that could explain the bad behaviour.

Of course there may well not be anything visibly broken.

A bad solder joint might be seen, maybe with magnification. 

PM me anything showing the circuit board, if you get in there for a look, please. 🙂

[nta16]

Please note - I am not a mechanic or expert in anything.

 

On 07/01/2023 at 18:23, lello7 said:

I can not attach any more pictures in this therad 😞

If it is a site issue Freedom membership might resolve that. - https://www.briskoda.net/forums/subscriptions/

 

Edited 9 January, 2023 by nta16

[lello7]

Update

I now have a new unit, but have not had the time to test it. I need to program it first (among others the radio code is stored there?)

Is it only possible with vcds or is there an cheaper option? I will have to rent regardless, but n vcds near me available. 

Mean while, I disconnect the battery and bring the Bcm with mee inside if I leave the car outside for a longer period of time. 

 

The bcm bord looked flawless under 10x microscope magnifying. 

I did resolder all pins 73a and 73b, and all relays... Same problem. 

This is a multilayered PCB, so I guess its a internal crack or bad connection between the layers. 

 

Any sugestions. I have all diagram for the car, but the actual relay is not presented. Only the connections going to and from it, j519 unit. 

 

 

[lello7]

The BCM change fixed the problem. Thank you all!