The protocol file indicates that your bed thermistor is working accurate as it shows the same temperature as both extruders. However, nothing happens when the heatbed is powered on which points to an electrical problem of the heatbed.
In case you or a trusted person can handle a multimeter this is what you can try:
- Unscrew the heatbed cables on the motherboard & measure the resistance of the heatbed. A working heatbed (assuming the 220 W / 24V type) should show roughly 2.6 Ohms resistance. If that is the case: Check if the resistance changes when wiggling on the connector cable near the heatbed. If that is the case: You’ll need to re-solder the cables at the bed solder connectors. Here is an example for the SV06.
- If there is no connection at all (infinite resistance): Check the solder connectors on the bed.
- If the bed solder points are OK: Measure bed resistance at the solder points between + and - connectors. If there is no connection: You’ll need a spare heatbed. If the resistance is close to 2.6 Ohms: Measure bed power cables between hotend solder point and motherboard cable end. In case of no connection: You’ll need to replace the cables between motherboard and heatbed.
Good luck
Björn