HELP!! Air pressure gauge issues

I think it is behind the center cup holder

 

I'm not overly familiar with those dashes but I believe those gauges are "dumb", they only read what the computer tells them to. Computer could be receiving the wrong info from the sensor circuit and then relaying that incorrect info to the gauge.

 

I was thinking as well

 

I don't know how to post a new thread. I have a 2009 Kenworth w900 the secondary air gauge shows 150 psi all the time. I put a new gauge in and that doesn't work either. But when I switch the wires to the primary air gauge it shows the correct pressure ‍♀️

 

was this issue ever resolved ? Having the same exact issue

 

No I haven't figured out what's going on yet

 

No worries
I read your posting and everything you mentioned is happening here on this truck as well

 

Z
Dealer In Lakeland says she had one in like that and it was one of the sensors needed replacing. Any updates?

 

That's an idea, I don't understand how it shows the correct pressure when the wires going to the gauges are switched. Does the ECM or whatever is sending the signal know the difference between a primary and secondary air gauge?

 

I wouldn't think so. It's not smart enough to have 25 computers like the latest PACCAR over complicated monstrosities. I did see separate sensors labeled primary and secondary air pressure. Also Parking Brake air psi etc. Just check Amazon or Fleetpride before the dealer. They wanted $341 for brake app. sensor. Fleetpride is getting it next day for $89. Also another member here sent me a link to Amazon for $18.97 so l ordered three of those for spares