Ctis issues

[mark robin]

I have a 1078 and when I'm up and going the Ctis box starts to click and lights start blinking if I push one of the buttons it stops making noise for awhile but starts shortly after when I go to shut down the air starts to come out by the frame rail kinda by the fuel tank making a squealing noise until it runs low on air any idea what's going on ?funnything is that it seams that ctis works at times because it will air down and overspead light will come on if your going to fast I hope somebody has maybe run across this before

 

[mark robin]

​ctis issue

 

[Coffey1]

Pull the pcu take it apart clean it check the solenoid coils to make sure they are good. Put it all back together the way it came apart.

 

[Suprman]

Clean the pressure protective valve on the right side of the air tank by the ctis pressure switch. Service or upgrade your air dryer.

 

[mark robin]

coffey can you explain where the pcu is I'm a fast learner

 

[mark robin]

thank you supermen is there a schematic that would show me what valve looks like also pressure switch any idea cost on upgrading dryer?

 

[DiverDarrell]

Schematic is in the TM's. It's best to download all of them. Some day I plan on taking the files to get them printed.

 

[coachgeo]

thank you supermen is there a schematic that would show me what valve looks like also pressure switch any idea cost on upgrading dryer?

search will answer most these questions.... including on how to get ahold of Will AKA suprman for a price on dryers if he still has them.

 

[birdslinger]

Any updates on fixing this issue Mark?

Mine started acting up and all three issues started at the same time.....
1. CTIS highway light flashes constantly even on long trips. It expels air 5 seconds on, 5 seconds off
2. When you shut the truck down, the front and rear CTIS valves start expelling air. It happens right when you kill the truck. Sometimes they stay open until the tires are flat, sometimes close within 20-30 seconds. When you crank the truck back up the tires fill right back up to highway level.
3. The air pressure relief valve for the main system now sounds like a screeching firecracker instead of a loud hiss.

 

[Suprman]

Fill all your tires up with the truck off. Take off the banjo bolt and put plastic bag scrunched down over the banjo/hose end. Rubber band down right. If the bag expands you have air leaking thru your wheel valves and they need to be replaced. Check this first and then we can go from there.

 

[Andyrv6av8r]

Any updates on fixing this issue Mark?

Mine started acting up and all three issues started at the same time.....
1. CTIS highway light flashes constantly even on long trips. It expels air 5 seconds on, 5 seconds off
2. When you shut the truck down, the front and rear CTIS valves start expelling air. It happens right when you kill the truck. Sometimes they stay open until the tires are flat, sometimes close within 20-30 seconds. When you crank the truck back up the tires fill right back up to highway level.
3. The air pressure relief valve for the main system now sounds like a screeching firecracker instead of a loud hiss.

See post #3 above. Been there, done that on Coffey's truck and it fixed his. Sounds like your deflate solenoid is sticking, as in dirty.

 

[carc383]

thanks for info i will try if time permits later today when i go to my shop