M923A2 broken air switch? Something else?

[rjk]

I crawled under the truck today to look for an air leak, but found this as well:





It appears to be a pressure switch that has broken off. However I'm not sure what it is exactly. Here's the interesting part: In the P2P program, I found a picture of that area, and the same part was dangling down and appeared to be broken in the same way - I assume it's either a) not broken, or b) a common failure. Anyone have any ideas?

 

[4XDesign]

If I'm not mistaken my 925 has the same piece broken. Not sure what it effects.

 

[74M35A2]

Is that the 60psi pressure switch for the warning bell? Would be my guess, has wires on the harness and plugged into air system.

4x I blame you for my spending of $440 today for a brand new Volvo 8181250 full size 14L charge air cooler, same one you installed.

 

[rjk]

The switch in the picture is on the wet tank inside the frame. The two low air warning light switches are on the primary and secondary brake tanks that are stacked up on the passenger side of the vehicle, and are working correctly as far as I can tell.

 

[Andyrv6av8r]

It's for the CTIS. At around 120 psi it tells your ECU to do a pressure check.

 

[rjk]

It's for the CTIS. At around 120 psi it tells your ECU to do a pressure check.

Awesome, thanks for the tip. I was able to find it in P2P (P2P-M12), and it says this:

The Air Pressure Switch Assembly monitors the air pressure in the pneumatic system and disables the CTIS when the air pressure is below 85 PSI. The CTIS will remain disabled until the air pressure measures 120 PSI.

So I guess that could explain some of the CTIS issues. Now I need to find a part number and replacement part for this thing.

 

[therooster2001]

This is quite an elusive part online, here is the part number. The only one I found, I pulled off myself in a salvage yard.

Dana Spicer Tire Inflation Pressure Switches 673345 NSN 5930-01-446-9234 CTIS

Some people have deleted their CTIS, and probably have it wired still, maybe they could help. Be very careful taking it off, a piece of the end after the green part looks like a nut, but is plastic and is really fragile. The real other end of this is a pigtail that connects via a cannon plug, make sure you get the whole thing.


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[rjk]

This is quite an elusive part online, here is the part number. The only one I found, I pulled off myself in a salvage yard.

Dana Spicer Tire Inflation Pressure Switches 673345 NSN 5930-01-446-9234 CTIS

Some people have deleted their CTIS, and probably have it wired still, maybe they could help. Be very careful taking it off, a piece of the end after the green part looks like a nut, but is plastic and is really fragile. The real other end of this is a pigtail that connects via a cannon plug, make sure you get the whole thing.


Sent from my iPhone using Tapatalk

AWESOME!! I've literally spent the last hour and a half googling like a madman trying to find this thing, and came up empty-handed. Thanks very much for providing the numbers for me. Cheers!