Can you find out the resistor's value?

[AKnogood]

I'm trying to fix a 5 years old dishwasher board that burned. One electrolytic capacitor dried out so I'm replacing all of them on the board (5) but there's also a resistor which I think is a high power resistor that I would need to replace. How can I know what value it was since it burned?

 

[ard]

Try desoldering it; there's a small chance the band colours might be visible on the underside. Even if you can discern just the third band (before the golden), you'd have a fair idea of the value.

 

[AKnogood]

I desoldered the resistor from the board but unfortunately the band color is completely burned. I tested the resistor using an Ohmmeter and it showed 42Kohm. Is it reliable even though the resistor burned?

- - - Updated - - -

I was able to find a picture of the electronic board online. The resistor is located at the bottom right (R189). I think the bands are orange - brown - black (31ohm), what do you guys think?

 

[BradtheRad]

You may be able to rule out a range of minimum values. Figure out what amount of power would exceed its watt rating.

The resistor's size indicates its watt rating. From the photographs it looks like 1 or 2 W.

Example, if the voltage is 5V, then current through 31 ohms calculates to 5/31, or .16 A.
This makes 0.8 W of heat on the resistor.

See if you can get a volt reading across the resistor. Test both DC and AC.

Or, make an estimate by examining its connections to neighboring circuitry.

 

[FvM]

Unlikely 31 ohm, it should be either 33 or 22. Wirewound power resistor have at best E12 series values.

 

[betwixt]

From it's position on the board it looks like it's an inrush current limiter so the value is likely to be in the 30 Ohms region. It could be 31 Ohms but as other point out, it is more likely to be one of the standard values than one specially made for the board.

Intuitively, I would go for 33 Ohms, the chances of it causing problems if a few Ohms one way or the other are slim. It could even be 27 Ohms (Red, Violet, Black).

Brian.