2003 international secondary tank gauge issue

I have 2007 international workstar 7400 the primary air gauge pointing down to 6 o’clock
position and buzzer is on. All other gauges are
normal. Has code SPN 1087 FMI 0 so I changed the primary air tank transducer under dash and that didn’t fix problem. So I swapped
connectors on primary and secondary transducers and symptom didn’t carry over to secondary air gauge nor did the primary start working correctly. I manually checked air pressure in tanks and it’s normal. Been driving truck for a couple days just buzzer is annoying.

What should I be looking for now?

 

The air gauges on the panel should be able to be replaced.
If you swapped connectors between the gauges and the problem
did not change its most likely the gauge.

 

changed gauge didn’t fix problem. Body controller?