e89 roof problem

[Pondrew]

Well what do you know, second (left hand side) one has two resistors attached!

The switch without the resistors was the one that was faulty, there was some discolouration of the contacts internally, possibly due to arcing. Therefore I think the switch had been over-heating and melted the solder from the resistors. When I pulled it apart, the resistors fell out without me noticing.
Thanks Robbie, your knowledge is peerless and I have found this really interesting (apart from spending an hour sorting through a box of rubbish trying to find two tiny resistors which I didn't)

IMG_8304.JPG (53.78 KiB) Viewed 905 times

[RobbiZ4]

... the switch had been over-heating and melted the solder from the resistors ...

No, never ever.

Just have a look at Wikipedia, which temperature is required to melt the solder. Much earlier the surrounding plastic would have been melted.

But - black or green or at least coloured traces in electronic components ar mostly signs of (water) corrosion.

[Pondrew]

So the mystery of the disappearing resistors looks like it will never be solved (or soldered).

[flybobbie]

Place i worked had smd soldering equipment. Circuit board had a template placed on top with small holes and solder powder was brushed into the holes.
Template was lifted off leaving small mounds of powder, then smd's were pick and placed by machine on the powder. Then went through oven to bond.
I would say some poor amounts of solder or quality with result a weak bond, resistors from vibration falling off.

[Pondrew]

Place i worked had smd soldering equipment. Circuit board had a template placed on top with small holes and solder powder was brushed into the holes.
Template was lifted off leaving small mounds of powder, then smd's were pick and placed by machine on the powder. Then went through oven to bond.
I would say some poor amounts of solder or quality with result a weak bond, resistors from vibration falling off.

Makes me feel better. I am having sleepless nights over the vanishing resistors

[Ole gits rule]

Place i worked had smd soldering equipment. Circuit board had a template placed on top with small holes and solder powder was brushed into the holes.
Template was lifted off leaving small mounds of powder, then smd's were pick and placed by machine on the powder. Then went through oven to bond.
I would say some poor amounts of solder or quality with result a weak bond, resistors from vibration falling off.

Snap with that, I worked with Fuji machines and the patterns for adding solder were normally good until someone let the paste run low or the oven temp was not correct.

[Ole gits rule]

Place i worked had smd soldering equipment. Circuit board had a template placed on top with small holes and solder powder was brushed into the holes.
Template was lifted off leaving small mounds of powder, then smd's were pick and placed by machine on the powder. Then went through oven to bond.
I would say some poor amounts of solder or quality with result a weak bond, resistors from vibration falling off.

Makes me feel better. I am having sleepless nights over the vanishing resistors

You sure you're still not going mad and we are all making this up

[flybobbie]

https://www.youtube.com/watch?v=tQHDSXDZYF4
https://www.youtube.com/watch?v=T2SK30JRs_E

[RobbiZ4]

Well,
It's a 10 seconds DIY job, if you follow my instructions on ZROADSTER.COM.
No tools are required, the battery can stay connected, no video to watch, just read my posting.

https://www.zroadster.com/forum/threads ... st-3124720

[Pondrew]

https://www.youtube.com/watch?v=34_Wa3tXVMg
cheap and simple maintenance fix and recommended every 5 years or so.

That's great but this thread was about micro-switches not salmon relays.

[RobbiZ4]

...this thread was about micro-switches not salmon relays.

Indeed.