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Maintenance thread teared down due to spam posts.

Appreciate your time to pull together all your previous help into one place.
Thank you.

Great resource..probably will save n thousand posts per year (well maybe)..

Pbondar wrote: ↑Wed Aug 18, 2021 9:12 am Great resource..probably will save n thousand posts per year (well maybe)..

But then it gets boring in this forum and I might only come back by once a year for the annual BONGfest.

enuff_zed wrote: ↑Wed Aug 18, 2021 8:02 am Appreciate your time to pull together all your previous help into one place.
Thank you.

Agreed.

Any fault obd saying it's a Hall switch, probably a break in the wiring or a connector loose.
That was the two roof faults my car has had.

flybobbie wrote: ↑Wed Aug 18, 2021 7:43 pm Any fault obd saying it's a Hall switch, probably a break in the wiring or a connector loose.
That was the two roof faults my car has had.

Yes, but this is a bit tricky! The CTM partially notes down a wrong(!) hall sensor fault, if a timeout occurs. Nonsense, sourced by the microswitches coupling lock.

RobbiZ4 wrote: ↑Wed Aug 18, 2021 8:07 pm

flybobbie wrote: ↑Wed Aug 18, 2021 7:43 pm Any fault obd saying it's a Hall switch, probably a break in the wiring or a connector loose.
That was the two roof faults my car has had.

Yes, but this is a bit tricky! The CTM partially notes down a wrong(!) hall sensor fault, if a timeout occurs. Nonsense, sourced by the microswitches coupling lock.

Yes when i replaced salmon relay the obd readout said there were five faults on hall and microswitches (there were non).
All cleared after i replaced the relays.

Salmon relay (part no. 12631742690)

Helpful post. For ease of reference maybe it needs to made a sticky / pinned.

RobbiZ4 wrote: ↑Wed Aug 18, 2021 11:39 pm Salmon relay (part no. 12631742690)
Relais Hardtop-Antrieb K18363a und K18364a(1).jpg

Robbi, brilliant change of avatar.

Something that never registered or noticed when i opened up relay, was the rectangular object molded on the case paralleling the coil.
Is this a suppression diode or a continuity check resistor?

flybobbie wrote: ↑Thu Aug 19, 2021 6:43 pm Something that never registered or noticed when i opened up relay, was the rectangular object molded on the case paralleling the coil.
Is this a suppression diode or a continuity check resistor?

It's a small resistor with about 80 ohms.

RobbiZ4 wrote: ↑Thu Aug 19, 2021 6:58 pm

flybobbie wrote: ↑Thu Aug 19, 2021 6:43 pm Something that never registered or noticed when i opened up relay, was the rectangular object molded on the case paralleling the coil.
Is this a suppression diode or a continuity check resistor?

It's a small resistor with about 80 ohms.

Does that act as a 'damper' to stop arcing?
Same as a condenser on an old points ignition system?

Well a diode would be used to prevent back emf destroying any transistors driving the coil, coil acts bit like ignition coil.
Fairly standard practice with relays on dc circuits.
Resistor might be used to check circuit continuity for monitoring purposes.
Could these resistors break down causing roof to stop.
My roof just stop on relay "failure".
My obd reader said relay failure, it's how i found out to replace the relays.

I tested relays on bench, they worked fine, hardly any resistance on contacts.
But does resistance of coil connections vary from faulty and new.