M35A3 CTIS

[ohfiredude]

Can I disable the CTIS in my M35A3 without having any problems with my tires?

Thanks!
Dave

 

[kblazer87]

I think you will need to replace the tire air hoses with regular schrader valves and cap off the ctis or remove it, but yes many have done just that.

 

[KN6KXR]

If all the components are good: yes. Is it fully functioning?

Just unplug the controller. You may have some leak by in the wheel valves over time as it's just another way for air to get out. Otherwise should be fine. The wheel valves won't open unless given a pulse of air by the controller and if that's unplugged.....

I really like the CTIS on my wrecker. It's worth keeping. I use it for recovery work (friends who get their tractors stuck and stuff). Super handy.

 

[ohfiredude]

If all the components are good: yes. Is it fully functioning?

Just unplug the controller. You may have some leak by in the wheel valves over time as it's just another way for air to get out. Otherwise should be fine. The wheel valves won't open unless given a pulse of air by the controller and if that's unplugged.....

I really like the CTIS on my wrecker. It's worth keeping. I use it for recovery work (friends who get their tractors stuck and stuff). Super handy.

KN6KXR,

Thanks! I did install a new CTIS controller, but it still doesn't work. Any ideas besides a bad power connection?

Dave

 

[ohfiredude]

I think you will need to replace the tire air hoses with regular schrader valves and cap off the ctis or remove it, but yes many have done just that.

Can I disable the CTIS in my M35A3 without having any problems with my tires?

Thanks!
Dave

Mike,

Thanks!

I replaced my CTIS controller with a new one, but it still doesn't work.

Dave

 

[Mullaney]

Mike,

Thanks!

I replaced my CTIS controller with a new one, but it still doesn't work.

Dave

.
There is a CTIS troubleshooting thread (link below). There is a DANA / Spicer troubleshooting guide here in the TM section too. Another idea is to replace the controller that you bought with a more "manual" version of that part.

M1078 fmtv ctis

hi all I have a 1995 M1078. the tires hold air pressure but the highway light flashes on the console. If I press another setting nothing happens but the light flashes. Any ideas on were to start. I have not found any air leaks thanks

www.steelsoldiers.com

CTIS and Arduino

Here's the A1R cannon connection and model number as per your msg. I'm 99.99% sure that it's the same connector as the A0 and A1 trucks use.

www.steelsoldiers.com

AND if you just want to remove CTIS completely, that is definitely possible too.

 

[KN6KXR]

I suggest you down load and run the M939 series P2P program and study the CTIS section. I know it's not your truck but the CTIS theory will be the same. It's super helpful to understand exactly how it works. It's animated..... You'll have to play some computer tricks but I got it to work with Windows 7. Anyways it really helped me I think it will do the same for you.

Second thing is if your going to go after the CTIS you'll need a shop air supply, that won't be loud, at 120psi to run the truck. You can't track the leaks with the motor running. You need a fairly quiet environment to look/listen once you get it going.

Third thing is get all the info. There's tons of it. Troubleshooting manuals, wiring schematics for the truck, Dana CTIS manual, etc, etc... Everything you need is available.

Fourth thing is, once you understand your system, make the test tools and carry them and a blank line kit. The problem with the CTIS is if you lose one wheel seal they all go flat. So if you get a failure having a test tool (adapter and gauge with tank valve) and a line plug is essential. Then you can identify and run with 5 of 6 wheels operational and hand set the 6th pressure. I had to use this once when on a road trip one of the supply lines failed. Works great kept rolling.

For your current issue get the CTIS manual and pin out the supply. You've swapped controllers already (and they do go dead happened to me) so the next stage is walk the pins with a meter. Pretty sure this is in the CTIS manual. Get the power up issue solved first.

Keep in mind guys have built their own CTIS controllers from manual toggles and gauges. It's not that complicated. That's why you should study the M939 animated program. My M936A2 had a broken CTIS and I drove it from MI to CA without issue. Once I got home I went through a controller and 4 hub seals to get it fixed. I did some other stuff on the way like make my tools and swap some fitting types to keep all wheels the same. In the end it was 99% grunt and 1% head scratching once I got going.

Hope that helps.

 

[DeMilitarized]

I suggest you down load and run the M939 series P2P program and study the CTIS section. I know it's not your truck but the CTIS theory will be the same. It's super helpful to understand exactly how it works. It's animated..... You'll have to play some computer tricks but I got it to work with Windows 7. Anyways it really helped me I think it will do the same for you.

Second thing is if your going to go after the CTIS you'll need a shop air supply, that won't be loud, at 120psi to run the truck. You can't track the leaks with the motor running. You need a fairly quiet environment to look/listen once you get it going.

Third thing is get all the info. There's tons of it. Troubleshooting manuals, wiring schematics for the truck, Dana CTIS manual, etc, etc... Everything you need is available.

Fourth thing is, once you understand your system, make the test tools and carry them and a blank line kit. The problem with the CTIS is if you lose one wheel seal they all go flat. So if you get a failure having a test tool (adapter and gauge with tank valve) and a line plug is essential. Then you can identify and run with 5 of 6 wheels operational and hand set the 6th pressure. I had to use this once when on a road trip one of the supply lines failed. Works great kept rolling.

For your current issue get the CTIS manual and pin out the supply. You've swapped controllers already (and they do go dead happened to me) so the next stage is walk the pins with a meter. Pretty sure this is in the CTIS manual. Get the power up issue solved first.

Keep in mind guys have built their own CTIS controllers from manual toggles and gauges. It's not that complicated. That's why you should study the M939 animated program. My M936A2 had a broken CTIS and I drove it from MI to CA without issue. Once I got home I went through a controller and 4 hub seals to get it fixed. I did some other stuff on the way like make my tools and swap some fitting types to keep all wheels the same. In the end it was 99% grunt and 1% head scratching once I got going.

Hope that helps.

Check to see if your controller lights are activated by the headlight switch. Late model m939 controllers did not show any signs of life until the headlights were turned on.
Wouldn't the wheel valves hold the air in the tires individually until 7psi pop off pressure is hit?
From my experience if the controller has 5 lights it is a bad controller. IF it just does some weird stuff with the lights and does nothing could be a bad solenoid in the pneumatic control unit. A attempt to air the tires and then 4 lights flashing is a large leak. Hook to shop air and hit the runflat to bypass it. Then listen for leaks near the QR1 valves and the wheel valves. IF you hear it near the back side of a wheel on the inside part of the tire it is likely a wheel seal. Not to hard to fix. If you have no power to your controller check if there are any fuses to the controller and see if they are blown.

 

[glcaines]

Can I disable the CTIS in my M35A3 without having any problems with my tires?
Thanks!
Dave

All you have to do is turn off the controller. I have an M35A3 with CTIS. My CTIS works great, but I keep it turned off because the CTIS will only inflate the tires to 45 PSI. I normally run 60 PSI in my tires as the truck drives better. The redline pressure for the Michelin wheels on the A3 is 60 PSI. You just manually add air to the schrader valves on the wheel cylinders if you need to add air. By the way, never turn your CTIS on when the weather is cold without driving first and warming the hubs up to protect the hub seals. I normally run at least 30 minutes in cold weather before turning on the CTIS. I can't remember the recommended driving time in the TM. The CTIS system on the A3 is very simple. Read the TM troubleshooting section and you can identify your problem.

 

[KN6KXR]

I only have the M939 series to compare to so take it with a grain of salt but the following from that:
-The 5 flashing lights means a TON of stuff. Look in the Dana CTIS troubleshooting guide I believe it's still available for download from their website. The only controller I lost failed to light up after previously being lit.
-On the M939 series there was a blackout input that was triggered from the headlight switch but only on later model controllers 676422 and 676603. These boxes were black. Previous version boxes, painted green typically, light up as soon as the ignition is switched.
-In the later part of the CTIS rollout there was some "half finished" work. My data plate indicates TWO different tire pressures for different terrain. The truck came with a single channel controller and more importantly only 3 pnuematic valves. If it were a two channel system there would be 5 valves. So they made the plates but never got around to fitting the controllers and hardware.
-If you have one of the later boxes that has the J1939 interface you can make an adapter cable, break it out and talk to it. The freeware from Dana works well. You'll need a 24V Dearborn adapter I used one from a surplus STE/ICE kit and the serial port on a laptop. I can program the pressures for the modes, the overspeed indicator for each mode, etc.. Only problem I have with the Wrecker is the software won't let me go over 80psi for HWY and it should be 90psi. There is a challenge code it asks for so I can go over 80 but the folks at Spicer won't get back to me. I've only bugged them a couple times I'll keep trying maybe I'll get lucky and find somebody who can actually help.
-The supply lines on my M936A2 were SAE in the front and JIC fittings in the rear. Yes I checked the -34P they are correct. I changed them all to JIC my local hose shop had the fittings. Now the tool I made can work on all of them.
-The tool I made is just like the one in the TM. It has a male inflation line fitting, a tee to a blowoff valve, a gauge and a tank valve. I adapted a gas pressure test setup from Home Cheapo. Put a 100psi gauge on there. My truck is supposed to hold 80psi for some length of time.... if it leaks it'll leak right away. I bought a cap for the setup. If I'm in the field and have a failure it gets tested then the cap that normally goes on the tool goes on the line and I can run with 5/6 on CTIS and the last one manual. For sure this: running around listening for air escaping sucks! The M939 drums are huge. Good luck. The test tool nails it dead certain. Totally worth the effort.
-The hub seals aren't hard. They make a special setting tool but it's pretty obvious where they go. The hard part for me is a 37,xxx pound truck, 10 lug nuts at 450 foot pounds, caging the air brake and wrestling a 14r20 tire.

All I can think of at the moment. Hopefully some of that was helpful.

 

[HDN]

If you're not going to use the CTIS and have no desire to maintain it, just disconnect the CTIS wheel valve hoses from the tire and put a tank/Schrader valve at the 90 degree fitting off the tire inflation pipe. I removed the valves and counterweights when I put 395s on my truck. You may not be able to remove the counterweights without removing a tire clamp ring nut, which I don't recommend doing with the tire inflated.

If you're unable to remove the counterweight at this time, leave the wheel valve in place and cap all openings to prevent debris from getting into the wheel hub and CTIS valve.

If you're having trouble getting the CTIS controller working, I believe a place to check is the electrical connections at the power manifold. Mine's never worked and I never bothered to troubleshoot it since I don't use it.