I figure it will be the same as the 524 and a symptom can be rx OK. But no fan/xmit.
They are a problem to get to and work on. To do it properly you need to remove the front panel and the step-by-step instructions are in the service manual. FOLLOW THEM EXACTLY! Be particularly careful of the multi pin connectors when reassembling as it is easy to bend a pin and then break it - experience speaking.
If you remove front and/or back panels be VERY careful to keep the gears in alignment.
If you are not comfortable working with this gear, get it done. I posted some time back contact details for a guy in the US who does these sets.
If you are careful you may be able to put insulated probes onto the circuit breaker (there are two breakers) and check for continuity.but watch out as there is a high risk of shorting the power and also doing other damage.
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