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air gauge on 2003 U320

Would somebody be so kind to tell me where the electric signal to the rear air gauge comes from. My rear air is pegged at 180, switched gauges and the same. Thanks Tom
Tom and Nancy Johns
2003 U320 38ft. build #6223
Motorcader 17343
2024 Silverado trail boss
Carolina Shores, Nc

Re: air gauge on 2003 U320

Reply #1 –
Tom,

There are two air tanks underneath the front end of the coach.  On supplies air to the front brakes the other to the rear brakes.  An air line from each goes up into the dash in front of the driver's seat to the "blue module" where aire pressure is converted to an electrical signal which goes to the gauge.  Blue module failures are common.  The parts are likely no longer available.  Most just put a T in the air line and run an air line to a mechanical air pressure gauge.  See the following thread. 

"Blue Module" Failure

It is very unlikely that the rear tank actually has 180 psi. If you switched the electrical leads between gauges and the other also reads 180 psi then the likely problem is the blue box.

My 2001 was just before the blue box era, I had the gray box.  Same problem, similar fix with mechanical gauges.

Roger

Search the Forum for Blue Module

Look at that!  Thanks for the picture, Barry. 



Re: air gauge on 2003 U320

Reply #2 –
Quote from: Home2fromHastings –
Tom,

There are two air tanks underneath the front end of the coach.  On supplies air to the front brakes the other to the rear brakes.  An air line from each goes up into the dash in front of the driver's seat to the "blue module" where aire pressure is converted to an electrical signal which goes to the gauge.  Blue module failures are common.  The parts are likely no longer available.  Most just put a T in the air line and run an air line to a mechanical air pressure gauge.  See the following thread. 
"Blue Module" Failure
It is very unlikely that the rear tank actually has 180 psi. If you switched the electrical leads between gauges and the other also reads 180 psi then the likely problem is the blue box.
Roger
Search the Forum for Blue Module
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: air gauge on 2003 U320

Reply #3 –
Thanks very much. I guess mech gauges are in order. Tom
Tom and Nancy Johns
2003 U320 38ft. build #6223
Motorcader 17343
2024 Silverado trail boss
Carolina Shores, Nc

Re: air gauge on 2003 U320

Reply #4 –
Tom, I used VDO gauges.  They work fine and are easier to read than the originals.  White bulbs with red and green covers for those colors of back light.

http://www.egauges.com/SearchResults.asp?Search=150-105&Submit=Search

150-105 Black Front
150-106 Black Rear

You will need a 1/4" tubing kit or you can get the parts you need at a good hardware store (probably for less).  I needed to go directly to the tanks and of course one kit got to the front tank and I was 2' short to the rear tank.

Re: air gauge on 2003 U320

Reply #5 –
If anyone wants to mail one of these blue modules and the associated gauge to me I'd be happy to take a look.  Often these electronics can be pretty easily repaired by replacing capacitors and other bits.

Re: air gauge on 2003 U320

Reply #6 –
Thanks Roger, those are the exact ones I ordered yesterday.
Tom and Nancy Johns
2003 U320 38ft. build #6223
Motorcader 17343
2024 Silverado trail boss
Carolina Shores, Nc

Re: air gauge on 2003 U320

Reply #7 –
The curved side of the dash towards the window sort of snaps into place, no mechanical fasteners on mine which should be like yours.  It takes a thin prying tool (a couple inches wide) and some courage the first time you open it up and then what you need to get at is pretty much right there.  It pops up and out at the bottom first as I recall.

Roger