Hawkeyethenoo

Works on the test bench.

Works on the test bench.

Cheers, could be! I've had a look and it seems there is what looks like SAM modules on both front fuse box sides along with modules for the ABC etc on the N/S. It's going to an MB Indy to have it diagnosed with STAR or whatever, as I'm just chasing my tail and don't want to start fecking with things I know less than nothing about.  
The good news is the modules appear to have good access, so half the car doesn't need disasembling to get at them.  Bonus!

I thought that the W215 used a gateway module, not the later SAM unit?

I'm on the fuse box hunt now, have checked all three fuse boxes found thus far, front left and right and rear under rear seats. There's perhaps another one, according to this thread. But I've had both dash end covers off and it's not hiding in there.  The 3 fuses relating to the cluster are on the passenger fuse box and are okay drawing 12v.
All the fuses checked out, except a couple marked in red. Couldn't get a reading from them. Removed, checked and refitted, same.
Fuse box covers have remained on and closed, no obvious signs of previous water ingress which is good.
 

I'm on the fuse box hunt now, have checked all three fuse boxes found thus far, front left and right and rear under rear seats. There's perhaps another one, according to this thread. But I've had both dash end covers off and it's not hiding in there.  The 3 fuses relating to the cluster are on the passenger fuse box and are okay drawing 12v.
All the fuses checked out, except a couple marked in red. Couldn't get a reading from them. Removed, checked and refitted, same.
Fuse box covers have remained on and closed, no obvious signs of previous water ingress which is good.
 

Plugged the cluster back into the car and it's still not getting power. Thinking, with this and the headlights and indicators not working this could be a SAM module related issue.
https://www.mercedesmedic.com/mercedes-sam-module/
 

Works on the test bench.

The Machine passed it's MOT today, first time of asking since the last ticket to ride experied, Oct 2022. En route hame from MOT station, the instrument cluster went dim and then, stopped working completely. No gauges nothing, blacked out. That was the highs and the lows of today.
Bugger... Car drives fine, heater, windows all work fine. Headlights now come on with and stay on until the ignition is switched off, related, and the left hand indicators have ceased working, related.
Had a quick look at the 5a fuses for the cluster, there's three of them and they all seem, fine. Now parked up with the battery disconnected. Checked for fault codes, none, it's a wiring or relay issue, or the clocks have just packed in? Anyway, 12months ticket to ride was the mission achieved for today.  Focusing on the postivies.  It's still great to look at.

Works on the test bench.

Works on the test bench.

Good and bad news I suppose. Don't envy you tracing the wiring.

The Machine passed it's MOT today, first time of asking since the last ticket to ride experied, Oct 2022. En route hame from MOT station, the instrument cluster went dim and then, stopped working completely. No gauges nothing, blacked out. That was the highs and the lows of today.
Bugger... Car drives fine, heater, windows all work fine. Headlights now come on with and stay on until the ignition is switched off, related, and the left hand indicators have ceased working, related.
Had a quick look at the 5a fuses for the cluster, there's three of them and they all seem, fine. Now parked up with the battery disconnected. Checked for fault codes, none, it's a wiring or relay issue, or the clocks have just packed in? Anyway, 12months ticket to ride was the mission achieved for today.  Focusing on the postivies.  It's still great to look at.

Found a repair company much more local, Stirling. Will drop it off with them today so they can check it out and report back... Rather not post out in case it gets damaged or lost in transit.

i know few people need a firm shake..lol

Found a repair company much more local, Stirling. Will drop it off with them today so they can check it out and report back... Rather not post out in case it gets damaged or lost in transit.

Well that was easy, stereo removal key either side of the cluster, click, click, pull and removed. Remove single wiring loom plug and the job's jobbed. Next !

 

Battery fully charged, cluster connected and connector wiggled and nothing. The only light which seems to still work is the SRS system. Headlights still coming on with the ignition, turn signals now inoperative.

The Machine passed it's MOT today, first time of asking since the last ticket to ride experied, Oct 2022. En route hame from MOT station, the instrument cluster went dim and then, stopped working completely. No gauges nothing, blacked out. That was the highs and the lows of today.
Bugger... Car drives fine, heater, windows all work fine. Headlights now come on with and stay on until the ignition is switched off, related, and the left hand indicators have ceased working, related.
Had a quick look at the 5a fuses for the cluster, there's three of them and they all seem, fine. Now parked up with the battery disconnected. Checked for fault codes, none, it's a wiring or relay issue, or the clocks have just packed in? Anyway, 12months ticket to ride was the mission achieved for today.  Focusing on the postivies.  It's still great to look at.

Well that was easy, stereo removal key either side of the cluster, click, click, pull and removed. Remove single wiring loom plug and the job's jobbed. Next !

 

The Machine passed it's MOT today, first time of asking since the last ticket to ride experied, Oct 2022. En route hame from MOT station, the instrument cluster went dim and then, stopped working completely. No gauges nothing, blacked out. That was the highs and the lows of today.
Bugger... Car drives fine, heater, windows all work fine. Headlights now come on with and stay on until the ignition is switched off, related, and the left hand indicators have ceased working, related.
Had a quick look at the 5a fuses for the cluster, there's three of them and they all seem, fine. Now parked up with the battery disconnected. Checked for fault codes, none, it's a wiring or relay issue, or the clocks have just packed in? Anyway, 12months ticket to ride was the mission achieved for today.  Focusing on the postivies.  It's still great to look at.

The Machine passed it's MOT today, first time of asking since the last ticket to ride experied, Oct 2022. En route hame from MOT station, the instrument cluster went dim and then, stopped working completely. No gauges nothing, blacked out. That was the highs and the lows of today.
Bugger... Car drives fine, heater, windows all work fine. Headlights now come on with and stay on until the ignition is switched off, related, and the left hand indicators have ceased working, related.
Had a quick look at the 5a fuses for the cluster, there's three of them and they all seem, fine. Now parked up with the battery disconnected. Checked for fault codes, none, it's a wiring or relay issue, or the clocks have just packed in? Anyway, 12months ticket to ride was the mission achieved for today.  Focusing on the postivies.  It's still great to look at.

Have put the battery on the 6amp charger, will let that boil away overnight and re-test the cluster before committing to posting it out. Back of my mind saying could still be battery issue, but unlikely really.

Hope it's the cheap&easy fix... #fingerscrossed 👍

On mine the actual plug was iffy and needed a wiggle to get it working , same symptom , gauge cluster just vanished