Strange Electrical failure (now with video).

[rotorwings]

Posted earlier, but now I have more information on the problem:
- R300D
- Car will sometimes behave perfectly normally, start, etc.
- Car will sometimes refuse to do anything (as shown in video). No lights, dials, starting, etc.
- Sometimes when the car is running turning on an indicator, lights, or other electrical components will completely kill everything including the engine.
- The horn will always work.
- No voltage drop can be seen on the battery, so the battery itself does not seem to be the issue.
- I have charged the battery fully, cleaned all terminals and connectors.


Here is a video of the problem: https://www.dropbox.com/s/16jr2lq5z6ygbwg/CatElec....

Any help greatly appreciated!

[rotorwings]

Sorry, what does MFU stand for?

I have swapped the location (moved them around) of all relays in the fusebox to see if that had an effect, but it didn't.

[rotorwings]

Thanks. Do you know where I would find it if it exists?
I have an R300D (2012) with the push button micro-switch dash and a sterling immobiliser.

[rotorwings]

REALIST123 - I think you're right.

I've checked everything again with a new battery and got really excited because everything was working fine, but then it all started going haywire again.

Any idea what part(s) might be failing on the board? Are there ICs on it, or just relays? £175 is a lot if it turns out to just be a relay! I can't believe they don't make the relays replaceable.