Panasonic NN-SD670S - Starts as soon as door closes

[buefordTJ]

Model Number

NN-SD670S

Brand

Panasonic

Age

6-10 years

Hi, 4 months ago the problem I had with this unit was it would turn on when the door opened. It was a faulty microswitch attached to the door mechanism ... easy fix.

This time around the unit turns on (fan, table rotation, and heats the food) as soon as the door closes. Pressing stop on the control panel has no affect on it.

 

[buefordTJ]

Correction to earlier post, actually it doesn't heat the food.

 

[jeff1]

Hi,

NN-SD670S

Won't come up for me online.

Door switch, door switch mechanism, welded closed relay on the smart board are common trouble makers.
Definetly check the easy stuff ( door switches, door switch mechanism ) first.

jeff.

 

[buefordTJ]

Hi Jeff,

I would say it's the same as the newer model NNSD755S. Power output is the same.

Door switches were tested and passed. For the relay on the smart board i see two - RY1 a 4-pin relay (all soldered on PCB) and RY2 a 5-pin relay (3 soldered on PCB) ... see attached photo. How do you test these types of relay?

 

[jeff1]

How do you test these types of relay?

Some you cannot. Some can be ohmed. Some I will tap with a screw driver to see if the contacts will break apart....most times we just eliminate all other stuff until the board is the only issue left.

jeff.