Brake lights on. Dash indicator lights no flash-sound. Cruise light on. Brake warning

[wpoll]

I have heard of folk (on this forum) with an e53 where the sun-visor test DOES work - so it may be dependant on the exact fault...

Thinking about this issue, if there are electrical items that are running when the ignition switch is off (key out) then the ignition switch has to be the prime suspect. Any other explanation involves a much more complex electrical gremlin that seems unlikely.

In complex electrical systems most failures are connected to items that move, get hot or carry high voltage. If a component doesn't involve one or more of these conditions, it'll likely last a very long time.

In the case of the ignition switch (contacts module), it moves. It then wears and the connection resistances go up. If a connection is carrying high current and it goes up in resistance, then it can get hot. That's two....

[w3it]

Thanks for everyone’s input. Having disconnected the battery twice, l have not been able to reproduce the original faults. “Inspection” is on the dash and stays on for approximately 5 seconds after engine start. The “i” warning light stays on and l can read error code E30.

This might not be related but l also found these faults:
1 central locking button on consol does not work
2 no interior lights when door opened
3 central locking on key does not work but it does open the rear hatch

I found a thread where it was said that the keys were low in charge and he charged car over night with the key in the ignition. In the morning, the central locking worked! I will try that but that does not explain the consol button and the interior lights. Fuses 20, 24 and 60 are fine.

I did previously swap out the immobiliser unit ECU 61356905666, in an attempt to see if it fixed it. BUT l got them mixed up and now don’t know if the original is in the car or the purchased one. Either way, could that be the cause?

[w3it]

I was in the car just now and noticed that when I press the console lock button or the key remote, it activates the light near the gear stick. So at least that says a signal is getting through to the computer, right?

[w3it]

Have been away for a few weeks. Found a video on how to refurbish the ignition switch. Anyone following this thread, here is what l will be trying later today. Will update what the results were:
https://youtu.be/5sEfZIpE9h8

[Crowz]

Nice to see whats inside it but Id rather replace it myself aka new contacts.

[bcredliner]

The E53 switch is very different than the one in the video. Points are not nearly as robust.

It is likely a bad ignition switch in ones vehicle is the original switch. While the points can be smoothed that may not be the problem. The plastic 'ramps' wear down and can't be refurbished.

This is one of those parts that should be replaced with an OE or OEM part and drive on for another 100,000 plus miles. Not expensive especially if you consider risk of getting stranded with refurbished switch.