Samsung eco bubble spin failure

This thread was marked as solved. Here's a summary of the problem and the fix, generated from the discussion below.

Samsung WW90J6410CX not spinning, 3C motor fault

The problem

Samsung Eco Bubble washing machine model WW90J6410CX was failing to spin. The drum felt "lumpy" when turned by hand, but spun freely when the motor lead was disconnected. The original poster also reported that this behaviour was the same with the power on or off.

Likely cause

The discussion points most strongly to a fault in the motor circuit rather than a confirmed PCB fault, because the machine produced error code 3C described as a motor fault and the resistance to turning changed when the motor lead was disconnected. However, the exact failed component was not confirmed.

What fixed it

The recommended diagnostic step was to remove the belt and check whether the symptom remained, to separate whether the fault was in the motor, drum or belt. No completed repair was documented, so the exact repair was not confirmed. Further diagnosis should be carried out by a suitably qualified appliance engineer.

Checks to try

• Turned drum by hand with motor lead connected and disconnected
• Ran self diagnostic test
• Observed error code 3C
• Compared symptom with power on and power off
• Advised to test with belt removed

Parts or tools mentioned

• Belt
• Motor