GC1715 Temp Gauges Failure

[rScotty]

Hi, I have a MF GC1715 and i'm having problems with the temperature gauges. I found a previous post about diagnosing the problems with either the wire or the sensor, but both seem to be working. I have a connection from the dash connector to the thermostat, and the thermostat changes resistance as the tractor heats up.

Is there a way to test the gauge? I tried shorting the thermostat to ground and did not see a response on the gauge. I imagine I would have to replace the entire cluster which would be $$$ so i want to be sure.

Any ideas?

Lets back up a little bit here. Some things are not adding up.

The temperature gauge is composed of a sender, a single connecting wire, and the temperature gauge. Your cooling system does have a thermostat, but it is not connected to the temperature gauge, and I know of no way to measure the thermostat's reisistance....or if it even has a meaningful resistance.
So far, we are assuming that you meant to say "sender resistance" and just used the wrong term.
Can you attach a photo of the back of the gauge and of the sender?
rScotty

 

[Qmar]

Hey All,

Thanks for all the replies. I did a more through test on the weekend while i was patching up the driveway. I tested the sending unit cold, warm and hot and got resistance in range with the post above.

After screwing around with it for a week, driving it down a rough gravel road seemed to "fix" the problem, now the gauge is working. So am back to the bad wire/bad ground theory.

Based on the wiring diagram it seems the dash shares a common ground for all the gauges and functions and I haven't seen any other issues with the other devices so its either the circuit board or the wire. If/when it happens again I will bypass the wire and see if that fixes it. If not its in the gauge cluster.

As one poster above mentioned it might be the screws in the back of the PCB board. I made sure they were tight but i might pull them out and clean them and see if that does the trick.

Thanks again.

 

[rScotty]

Hey All,

Thanks for all the replies. I did a more through test on the weekend while i was patching up the driveway. I tested the sending unit cold, warm and hot and got resistance in range with the post above.

After screwing around with it for a week, driving it down a rough gravel road seemed to "fix" the problem, now the gauge is working. So am back to the bad wire/bad ground theory.

Based on the wiring diagram it seems the dash shares a common ground for all the gauges and functions and I haven't seen any other issues with the other devices so its either the circuit board or the wire. If/when it happens again I will bypass the wire and see if that fixes it. If not its in the gauge cluster.

As one poster above mentioned it might be the screws in the back of the PCB board. I made sure they were tight but i might pull them out and clean them and see if that does the trick.

Thanks again.

Good plan. I noticed that the poster you are referring to - the one who fixed his by tightening the screws on the PCB - just happens to have the exact same make and model of tractor that you do. And he had the same problem. And fixed it. And even posted a photo.
You don't get much better advice than that.
rScotty

 

[rossn]

Had a temperature gauge failure on my NEW GC 1715 tractor on arrival..... Found out the 3 screws that attach the printed circuit board to back of temp gauge were loose.... Check the screws for snugness....

View attachment 742728

I had a similar issue with my GC1705 gauge ceasing to work after many years. Screws were not fully snug but also not loose, per se. I removed, wire brushed screw and contact, and replaced/snugged (one-by one) and it works now. Thanks for the info.

 

[Mike1955]

All of the above suggestions appear to be written by some savy guys on this tech or computer stuff. The trouble must be either the sending unit, the cable going to the gauge or the gauge itself, which is a complete dash unit. So now swapping things is cheaper than taking it to dealer, and this is probably what they do. Sending unit is cheap so try that first if they have one. Or just put a old style on it in a different location. Good luck sir