Troubleshooting / Mesa Boogie Mark IV

[Turcs & Kaikos]

Hello all. My Mark IV has been working like a charm forever .... But as of tonight, it offcially went quiet ...

Where should I start ??


Thanks !

[Jazz P Bass]

Check the speaker?

[Enzo]

Check all fuses?


Tubes all lighting up?


ANy tubes turned white inside? (evidence of cracks)

[Turcs & Kaikos]

Thanks, I`ve tested two different cabinet, so we can exclude the speakers from the equation.

Tubes seems to be fine. Same for the fuse.

The problem is present irrespective of the channel and power mode (full / tweed)

[Jazz P Bass]

Here is the schematic.
Do you have a volt meter?
I would start by checking the power supply.(page 8)