What is this circuit for?

[DuncanS]

What is this circuit for? There was a completely fried fuse with melted plastic in the spot which is why I only put the red in part way to show what it is. The wires are red so assume a 30 feed. The aluminum matchbook beneath it is the window thermal circuit breaker. Upper left of the relay board.

Duncan

[VicVan]

Hi

What year?
If you have a Bentley it should be in there too.
_________________
'90 Little Blue Truck, 2WD auto, FAS GenV 2.0 NA (AVH)

[DuncanS]

Sorry, '91 tiptop weekender. There are no physical locations referred to in the Bentley and so no way to find what it does. I looked at all the 30 circuit paths and none are fused outside of the standard 1-22 fuses below the relay block. Clearly an OG installation as the feed comes directly from the 30 bus located to the left of the relay block behind the left most relays. The feed goes directly to the fuse holder and then disappears up towards the huge wad under the instrument panel. Too much of a rat's nest to figure out where it then goes. Since the remnants of the fuse were yellow, I have to assume it was a 5 amp fuse, but that may easily have been put in by the PO so we have no idea what the original rating was.

[syncrodoka]

It looks like the power harness fuses- windows/lock/mirrors.
There is mention of the fuse location and size in some years but not all in the bentley, the power harness also has it's own section in the wiring diagrams not part of the year diagrams.

[DuncanS]

syncro--Thanks. Looks like you are right about the central locking system. i live in the boonies and never even have to take the key out of the ignition, so haven't used the central locking system in years. Bently 97.227 shows the central locking system which is fused by fuse number 23. Since there are only 22 fuses in the main section below the relay panel, I have to assume this is it. Will replace with a new 20 A today and see what happens.

Could find no current path diagram or mention of mirrors anywhere in the indexes in the Bently. If you are correct, why would the mirrors need to be on a 30 circuit? I know German engineering is sometimes mysterious, but I would assume the mirrors would feed from 15. Especially if they have heated elements which should only go through 15 in that case. All odd. Does anyone know where to find the power mirror diagram?

Duncan

[ohhorob]

[crazyvwvanman]

The index page you should bookmark and put a tab on is 97.53 which lists all of the diagram sections for wbx models.

Mark

[DuncanS]

I'm well versed in the wiring diagrams and have become far more familiar with them than I wish. 30 and 15--yes, I know they only refer to a potential energy source and have nothing to do with current flow, either voltage or amperage. And Mark, thanks for the power mirror circuit diagram location. Wonder why it isn't in the main index in the front of the book? I've been spending some timy question. I have marked both 97.186 and 97.190 on page 97.203 where my '91 info starts......or at least used to think is stated. It took me awhile to realize that in DIN thinking, all digit numbers after the decimal point are sequenced ( 0-9 ) before going to the next place holder. In the beginning I assumed that 97.201 would follow 97.2. Wrong. 97.21 follows.

Put the fuse in the mystery location and tried the power locks, but none of the doors will accept the key!!!! What's this? I haven't changed any of the keys or location sets including the ignition, so am really baffled at this. The key goes in both front doors, but won't turn to even mechanically engage the locks. It won't even go in the slider. Didn't check the hatch as I took that electric lock out of the circuit when it wasn't working at the time of purchase 8 years ago.

Baffling

Duncan