[the-chauffeur]

A couple of weeks' ago, I experienced the HV battery glitch where immediately after charging the car reported that there was an issue with battery management (or similar) and it needed garage/dealer intervention. Freaked me out a bit until the car sorted itself out (after being left for twenty minutes) and I saw the number of posts on Reddit confirming that it's essentially a known issue.

Today it was the turn of the head unit to behave like it had a mind of its own. Turned the car on and although the screen of the head unit came to life, there was no sound. Checked a few things over, turned the ignition off and on again and still got no noise. Tried it again and the head unit died - no signs of life, no display, no response to button presses, no nothing. It was the sort of dead that looked terminal, but the way it went (with the sound first) suggested that it wasn't a fuse or loss of power.

Checked some fuses - there's four or five for the infotainment stuff so I'm not entirely sure whether I pulled all of them - but nothing untoward there. Tried off and on again and nothing. After much head scratching, I gave up and drove to where I needed to be in silence. Got to where I park up and put the car into reverse . . . and the reverse camera image appeared on the screen. Did what I needed to do and it went blank again. No nothing.

Put the car on charge and left it to do its thing for a few hours. Came back, put the key in and the head unit worked like nothing had ever been wrong. What the hell . . . ?

When it crapped out, I gave it a good look over because I've been messing about with adding a sub to the system and thought it was possible I'd dislodged something. The only wires I've chopped into are the speaker wires and there was nothing unusual to see. The only odd behaviour while the head unit was ahem, asleep, was that the sub was on. It's remote activated when the head unit is powered up (it senses power to the speakers) so I can only assume that the amplifier was on, and the remote camera image suggests some part of the screen was active. But I'm baffled as to why it packed up in the way it did, and even moreso that it's back to life now.

If this has happened to you, I'd be interested to know, but I guess I'm putting this here more as an information piece for anyone else who has the same issue. Basically wait for a bit and turn it off and on again . . .

 

[Laughing Crow]

My 451 with the Highline head unit did that a few times and now has worked flawlessly for over a year

 

[the-chauffeur]

Thanks Crow. Good to know. Unfortunately I think I have bigger problems now . . .

Mounted and wired in a set of rear speakers to the EQ. Fitting turned out to be more complicated than I thought it would since the speakers sit slightly proud of the mounts and the rear side of the rear liner plastics have standouts on them that look like they've been designed to fit onto/over a set of proprietary speakers. I'll need to fix one or other or both if I'm going to be able to remount the side panels without messing up the fit.

Anyways, ran everything for a bit off the head unit. To be fair, I ran everything quite hard/loud. And the right side has packed up. It lost a bit, then went out entirely. I've switched the wiring and it's not the speakers. And when I pulled the head unit to check the wiring, it was hot - very hot. I have a very bad feeling I've overloaded the right hand amplifier unit(s) in the head unit.

I've pulled the head unit out and taken it apart to see if there's anything obvious blown, but there's not all that much to see. It's fairly dense circuit board populated with lots of tiny components. There's one set that sit under a heatsink/fan that look like they might be amps/op amps, but components aren't my strong point. Suffice it to say that I can't see or smell anything that's blown/burned.

Yeah - I realise I need a decent power amp if I want to stick with the set-up I've got; I guess I was trying to see what sort of power the standard unit can put out (turns out a reasonable amount but not huge). Unfortunately I'm pretty sure I've just pushed it too hard.

Given the weird things the car has done so far, I'm kinda praying this is either a ghost in the machine or there's a thermal cut-out that I've tripped and that by leaving it for a few hours it'll sort itself out. But I'm also pretty sure that's wishful thinking.