Jandy JXi shorted temp sensor

Redduke916

Member
Nov 19, 2019
6
oldsmar, Florida
Hello All, Symptom is a temp sensor shorted message with temp showing 231. Sensor is 12K Ohms disconnected at the board and not shorted to ground. I left the wires off and powered up. The message is open sensor? When I reconnected and powered up, it showed normal temp for 10-15 seconds then went up till it opened.

So I assume the board is bad, even though it measured an open correctly. Can anyone confirm? Mt question now is, the part number of the board is E0256902 AG. I think the AG is a revision or tech number as all the boards I see to buy have a single letter "L""M" etc. but not an "AG."

Does anyone know how I can confirm the full correct part number or does it not matter?

Thank-you
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
15,697
Bedford, TX
Red,

I doubt the board is bad.. Just swap the air and water connections at the board and see if the problem follows the bad probe... If it does, the probe is bad, if not the board is bad..

Even if I thought it was the board, I'd install a new thermistor just because they are so cheap and the board is so expensive.

Thanks,

Jim R.
 
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Redduke916

Member
Nov 19, 2019
6
oldsmar, Florida
Red,

I doubt the board is bad.. Just swap the air and water connections at the board and see if the problem follows the bad probe... If it does, the probe is bad, if not the board is bad..

Even if I thought it was the board, I'd install a new thermistor just because they are so cheap and the board is so expensive.

Thanks,

Jim R.
Good idea. I will give it a shot. Thanks. However, my system does not use the coil/air temp input.
 
Last edited:

Redduke916

Member
Nov 19, 2019
6
oldsmar, Florida
I had a variable resistor and verified the board was good. After playing with the sensor wires, turning the system off and then on, the temp sensor finally went to 300 Ohms.
Hats of to you guys and thank-you for the help. I will get a new sensor.
 
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