BatteryTemp Sensor Stopped Working

[Resthome]

After 4 months of working the Battery Temp Sensor stopped working. Classic shows n/a 25 C and LA show no temp sensor connected.  Tried a brand new never open Midnite temp sensor and same thing. Checked the pins in the connector on the Classic and they all appear to be correctly aligned. Anyone else ever have the temp sensor on a Classic stop working?

[boB]

Try plugging in a phone cable that shorts all of the wires together.  This should cause the Classic's fans to
come on and show "battery hot" or something like that.

Also, there is a resistor (R17) that is right behind the phone jack that pulls the temp sensor up
to 3.3V  when unplugged.  When the sensor is plugged in, one side of that resistor will be at 3.3V
and the other end will be around 1.6V if the temperature is 25 degrees C.  Voltage will go down
when hotter and up when colder than this.

This assumes that you want to check the voltages of course.  Also, check the pins to make
sure they aren't bent katywompys.

boB

[Resthome]

Thanks boB   will check these voltages out when I return to the boat in a couple of weeks. 104 is just to darn hot for me so we fled back home to the A/C.

[Westbranch]

HMMM..... somethin' wrong here, up in the not so frozen North,  just back in from the cabin where it was 34C ( 93.2F)   and its 37 in town (100.4F)    ....  Well back to the lake next weekend!

[Resthome]

Westbranch...

I wish it was that way. Drought and hot weather don't go together. The price we have to pay to play.     Home is a nice 88 this afternoon.

[Resthome]

OK, when shorting all pins the fans run and it says “Battery Hot” .  The left side of R17 reads 1.5vdc and the right side reads 3.395vdc.  Replaced the controller and at first it still would not read until I replaced the Temp sensor also. Went back to check the original controller and it would not read with any of the temp sensors I have including the one that worked with the refurbished controller. I’m back in business with the new controller and a new temp sensor. So all is good. Very strange though that both turned out to be bad.

[boB]

Well, good that the fans came on and it said  “Battery Hot”.  That means that the jack is working...

But when your meter read 1.5 volts on the left of R17, was that with the short ?  It should read
somewhere around 1.5 to 1.6 volts or so with the BTS plugged in but with a short it should show
closer to zero volts.

[Resthome]

Well, good that the fans came on and it said  “Battery Hot”.  That means that the jack is working...

But when your meter read 1.5 volts on the left of R17, was that with the short ?  It should read
somewhere around 1.5 to 1.6 volts or so with the BTS plugged in but with a short it should show
closer to zero volts.

It wasn't with the short. But, I'm not sure if I had the temp sensor plugged in or not. It may have been open. What would an open jack have read?

[boB]

It wasn't with the short. But, I'm not sure if I had the temp sensor plugged in or not. It may have been open. What would an open jack have read?

Open should read the same on both sides of R17 or about 3.3 volts.

If you aren't seeing a real temperature while seeing around 1.5 volts on that one side
of R17, there must be a bad connection to the A/D multiplexor IC on the control board...
That is, if everything else is reading correctly.    Is the Follow Me enabled and/or BTS NET
in Follow mode in TWEAKS ?

[Resthome]

If you aren't seeing a real temperature while seeing around 1.5 volts on that one side
of R17, there must be a bad connection to the A/D multiplexor IC on the control board...
That is, if everything else is reading correctly.    Is the Follow Me enabled and/or BTS NET
in Follow mode in TWEAKS ?

No Follow Me was not enabled. So it must be something on the control board that went bad after working for 3 months. Thanks for the info boB.

[boB]

If you aren't seeing a real temperature while seeing around 1.5 volts on that one side
of R17, there must be a bad connection to the A/D multiplexor IC on the control board...
That is, if everything else is reading correctly.    Is the Follow Me enabled and/or BTS NET
in Follow mode in TWEAKS ?

No Follow Me was not enabled. So it must be something on the control board that went bad after working for 3 months. Thanks for the info boB.

Have you tried ~gently~ smacking the top circuit board maybe ?  I mean, to see if it's a bad connection  or bad solder joint maybe ?

If everything else is working normally and reading normally and you are seeing that ~1.6V on the one side of R17 but
it says N/A for battery temperature, then it sounds like the processor is not reading that sensor voltage on the
multiplexor chip, U20  above and to the left off the processor IC.    Plobabry...  Not nessicelary.