CTIS Zero lights....

[wheelspinner]

All my accessories work,no i have another issue.

I was referring to 1 Patriot, that's why I quoted his statement.

 

[k5ontherocks]

Ok, sorry, I was just adding my details as I seem to be having this same issue. Hard to find any info on it.

 

[1 Patriot-of-many]

If your PPV is stuck, you are not getting accesory air. Your gauges are only for the primary and secondary braking systems. Need to free that up first before CTIS will see anything.

Borrowed the PPV from the 923, still nothing. No cycling, no lights. Did find Spicer CTIS troubleshooting PDF in another thread, I'm hoping the speed signal generator missing from this truck will turn out to be the culprit.

 

[1 Patriot-of-many]

Mine lights up with the headlamp switch. However, mine has an issue now, its not just lights turned off. It had worked flawlessly for 2 weeks. Yes i used mine a lot, mostly just playing around in back field and such,but it had worked great till just the other day. The little diag i have found seems to point to bad ground or controller. i will check wirinig, but im skeptical i will find anything.

Can't find anything about the CTIS no lights in the TM's, but did find this in one of the threads http://dana.com/wps/wcm/connect/25f...=url&CACHEID=25f359804b1f69fba8acfff859534476

 

[k5ontherocks]

I have looked at the Dana info. It is some good info as well. It does have some diag info for "no lights" but looks like it all comes back to a bad ground or the controller. I am fairly sure mine isnt a bad ground because it will light up the indiacator as long as you keep holding the button,but goes out as soon as you let pressure off the button. I wil lbe working on it this weekend and report back if i find anyting.

 

[1 Patriot-of-many]

Same problem here. Only time I get any of the dots to light up is when I hold the button down. I get no cycling whatsoever. Yours cycle at all? I've got a couple other A2's so I might start substituting parts this weekend. Let me know if you figure it out before I do.

 

[k5ontherocks]

Same problem here. Only time I get any of the dots to light up is when I hold the button down. I get no cycling whatsoever. Yours cycle at all? I've got a couple other A2's so I might start substituting parts this weekend. Let me know if you figure it out before I do.

Nope, no matter how long i hold the button, no cycling. I wish i had another(for more reasons than parts swapping. haha) one thing i have learned. with the truck running, if i unplug the big connector on the back of the controller when i plug it back in the mode light will come on briefly, as well as the oversped light, and then goes off. Another thing,if i would push the xc button,just to test it, then unplug and reseat connector, the xc light comes on and back off,if i then push the hwy button and then unplug and reseat, the hwy button briefly illuminates. i hope thats understandable.To me this tells me ive got good power and grounds and the controller is seeing and recognising something,but still not working. gotta be the controller. I will mess with mine a little more before i just source a used controller. I will report back asap. Thanks for the info.

 

[1 Patriot-of-many]

Not recommended to unplug or plug in the ECU under power my friend. (I'm guilty myself trying to figure this out, but read not to afterwards). Hopefully I'll get a chance to start substituting parts from my tractor sometime this weekend when the sun does it's job

 

[brasco]

Looks like I have a truck with the same issue... No lights unless I hold a button down.

Did anyone ever determine what causes this?

Thanks,

Don

 

[1 Patriot-of-many]

Looks like I have a truck with the same issue... No lights unless I hold a button down.

Did anyone ever determine what causes this?

Thanks,

Don

Don, mine turned out to be the PCU, Pneumatic Control Unit. Under the shield to the right of the shift tower. I swapped that out with a take off someone sold me and presto, everything started working. I do have to have the head lights or park lights on on to see the dots working on this electronic unit. None of my other ones need the lights on to see the dots. No Terrain Lights or DDM – Dashes "--" (Codes 51, 52, 54, 55, 56)
Type: PCU Solenoid
(Supply, Deflate, Control, Front, or Rear)
Code Description
A “Solenoid Fault” code indicates an electrical fault in the
Pneumatic Control Unit (PCU). System operation is disabled
when these faults are detected.
The system shuts down in a fail-safe mode and turns off the
power to the solenoids.
The troubleshooting tree first tests internal solenoid circuitry.
Resistance outside the specified range of 30 to 80 ohms indicates
a defective solenoid. Succeeding steps check continuity
of the wire harness circuits between the PCU and the Electronic
Control Unit (ECU). If the problem can be traced to a
faulty circuit or connector, make the necessary repairs. If the
troubleshooting routine leads to a problem with the solenoid
itself, the PCU must be repaired or replaced. If both the solenoid
and the circuitry check out OK, the ECU is faulty.
See “Troubleshooting Tips” for general guidelines on system
diagnostics.
System Mode Condition Possible Causes (listed in order of likely occurrence)
No Operation PCU solenoid failed electrical
diagnostic test
• Solenoid wire shorted to ground
• Solenoid wire shorted to power
• Faulty solenoid
• Faulty ECU

 

[brasco]

Thanks for the update on this. I'll look into the PCU and see if this fixes it.

 

[1 Patriot-of-many]

The Spicer CTIS troubleshooting PDF was a help. Don't know if it's in the sticky, but do a search for the link and download it. I tested the pins on the PCU and it indicated a bad solenoid.
I see you have two A2's, swap the PCU from the good one if the pins test bad to check before you go buying one is what I'd do..

 

[brasco]

So... I pulled the PMU out this weekend and measured the resistance on the pins per the troubleshooting manual. Two of the coils are are OK but the control coil reads open circuit. Also... it appears that this coil has been replaced sometime in the past (old one cut off and spliced in with crimp connectors). Perhaps something is causing this coil to go bad. Anybody seen this before?

I'm now looking for a new coil to replace the old one. Does anyone know where to get these? The numbers on the coil are 5C-4211-P7 on one line with MR 7 below it.

I searched online but no joy. Somebody has to have these coils in stock somewhere? Where did the army get them?

Thank for everyone's help. I should have the M931A2 up and going soon with or without CTIS.

Don

 

[1 Patriot-of-many]

That's exactly what I was going to do when I purchased a take off from someone with a supposedly bad PMU. I tested the takeoff and it was good so i just swapped out the entire PMU. I'm sure someone would sell you a bad PMU cheap, Seems a lot of people just eliminate CTIS, chances are slim all three solenoids are going to be bad.

 

[brasco]

So... I pulled the PMU out this weekend and measured the resistance on the pins per the troubleshooting manual. Two of the coils are are OK but the control coil reads open circuit. Also... it appears that this coil has been replaced sometime in the past (old one cut off and spliced in with crimp connectors). Perhaps something is causing this coil to go bad. Anybody seen this before?

I'm now looking for a new coil to replace the old one. Does anyone know where to get these? The numbers on the coil are 5C-4211-P7 on one line with MR 7 below it.

I searched online but no joy. Somebody has to have these coils in stock somewhere? Where did the army get them?

Thank for everyone's help. I should have the M931A2 up and going soon with or without CTIS.

Don

I just wanted to post an update on this. I was able to find a coil that worked to repair the bad coil. I called the original manufacturer of the coil, Peter Paul. The said the part number I had was was very old but, unfortunately, they were not able to give me a good cross reference. I looked up a potential coil in the catalog and determined that a 5C-13-K24 coil would be close. I could have contacted a Peter Paul dealer for these but found some on ebay for a reasonable price.

The coil has a resistance of 85 ohms but was close enough for it to work. I tried to get resistance values from the manufacturer on other coil options but was not able to get the data.

It was actually pretty easy to replace the coil and splice it back in.​

 

[1 Patriot-of-many]

So it worked then?

 

[brasco]

So it worked then?

Yes. Once I put the new 5C-13-K24 coil in, everything worked just fine. The system started out with the flashing highwy light like it should. I ran the truck for about 1/2 hour and let the system do its thing. At first, I was concerned that the system wasn't working because it cycled several times before it really pumped the tires up. However, it settled into a long cycle and I eventually got a solid red light on the controller. I then measured pressure in all tires at 72 psi.

I can't say that these coils will work in everyone's system becasue of all the the variables but they worked for my system.

 

[1 Patriot-of-many]

Excellent!

 

[jcdostie]

Old post, old story. Same problem
Brasco is talking about PMU and 1 Patriot-of-many the PCU ???
Which one to check ?

Tks
JC

 

[brasco]

Old post, old story. Same problem
Brasco is talking about PMU and 1 Patriot-of-many the PCU ???
Which one to check ?

Tks
JC

JC,

I think I miss-typed in my prior posts. I was working with the Pneumatic Control Unit (PCU) on the floor of the cab. In this case mentioned above, I was able to identify and replace a bad coil. Apparently, they do go bad.

I have also had other issues with the CTIS system but at least the lights still work.
DB