M923 CTIS problem

[Bthrasher4]

I just purchased an M923A2 from Delaware...when I picked the truck up a couple of the tires were low (lucky I brought my Handy compressor - I filled the tires up). On the way home to North Western Virginia all 5 (five) lights were flashing and the alarm was sounding on the CTIS panel mounted on the shifter area. At that point I had no idea about how the CTIS system worked or what that meant (other than the alarm was irritating). So to make a long story short, the truck ran like a champ...averaged 55 to 60 miles per hour even up the grades on Highway 66 into the mountains (I know Virginia really doesn't have mountains, but that's what they call them). When I got home I ran a search on Steelsoldiers, here, and found this discussion...followed all the directions you masters of information provided and was able to get the system to work perfect (Bled the air out, restarted and did this a couple of times and now all the tires are maintaining pressure)...with no alarms...you all are the best and I consider you all to be better than any TM or blog...Thank you for your information, experience and knowledge...

Bob Thrasher
Front Royal, VA

 

[ichudov]

So, guys, being a soon-to-be owner of a M931A2 truck, I just have a very simple question: how difficult is it to disable CTIS and switch to regular manual airing of tires, if necessary? thanks

 

[Suprman]

You can take the hose to the valve off the front wheel stem and put in a schrader valve unplug the ecu and its disabled.
Thrasher- there is no audible alarm on the ctis just the 5 lights if you heard an alarm it was the parking brake and low air alarm I would definetly check on that if I were you. Do either of the red lights behind the steering wheel stay on?

 

[Bthrasher4]

No alarm for the CTIS?...OK. I can tell you both the idiot alarms and lights go off for the emergency brake and low air when both either reach the proper level or the brake is released. I have had 3 M923's and I know about the low air and brake alarms. The strange thing is there was a small alarm sound (3 people heard it and followed to the the CTIS box on the shifter stand). When I reset everything by bleeding the air out of the air tanks, repressurized the system twice and the tire pressure stabalized it stopped...not sure where, why or how, but it is not making noise any more...so I guess I should not be worried.

 

[1 Patriot-of-many]

No alarm for the CTIS?...OK. I can tell you both the idiot alarms and lights go off for the emergency brake and low air when both either reach the proper level or the brake is released. I have had 3 M923's and I know about the low air and brake alarms. The strange thing is there was a small alarm sound (3 people heard it and followed to the the CTIS box on the shifter stand). When I reset everything by bleeding the air out of the air tanks, repressurized the system twice and the tire pressure stabalized it stopped...not sure where, why or how, but it is not making noise any more...so I guess I should not be worried.

Maybe it's a Microsoft operating system.

 

[Suprman]

Maybe you had a small air leak hissing from the valve body you can just tighten the air connections.

 

[Burney]

Chadande, Would you have the pneumatic air solenoid
that goes in the floor. I bought mine and this was missing.
Haven't heard from anyone about having this part.

 

[Suprman]

That is the valve body. It controls inflate and deflate. Maybe you can get one of the ctis haters to sell you theirs.

 

[1 Patriot-of-many]

Chadande, Would you have the pneumatic air solenoid
that goes in the floor. I bought mine and this was missing.
Haven't heard from anyone about having this part.

Try TNJmurray, they seem to have everything I need for my A2.

 

[SLOrazorsedge]

Suprman how did the code checker device work out for you? Did you ever locate the correct plug-in portal? I just went thru the Spicer diagnostics CTIS TM and they definitely rely on thrown codes to narrow diagnostics. Anything leads on it is appreciated.

 

[Suprman]

I have a valve body from a 2010 rebuild. You need a y cable to adapt the ecu plug to run diagnostics. I am pretty good at troubleshooting the system without the diag though.

 

[bogshotrods]

Which TM would be best to look for trouble shooting the CTIS issues ?

 

[Artisan]

Which TM would be best to look for trouble shooting the CTIS issues ?

w/o knowing which ride you own it is hard, but try HERE.

 

[bogshotrods]

w/o knowing which ride you own it is hard, but try HERE.

Having a hard time navigating this forum, but my truck is an M923A2 and what is now happening is I don't get any lights at all on the control panel. Prior to yesterday I had an air leak at the drivers front wheel and it was just a loose fitting , with the HWY light blinking, tightened that up and now there's nothing, tried rebooting the controller and still nothing

Thanks so much for the link

 

[Suprman]

Turn on your headlights the lights on the controller should come on

 

[bogshotrods]

Thanks so much for the quick reply, I'll try that and hope it works .I just picked the truck up last Friday our in Barstow and it has 1200 miles on it and this is my first adventure with this kind of Beast. Yesterday after tightening up the loose fitting under the cover I had no lights on the controller , when I turned the electrical circuit on then hit the start switch all lights on the controller flashed for a split second then no lights, and when I tried to activate the CTIS to a different pressure setting nothing happened. Are there no fuse panel/circuit breakers in these things ??

Thanks again for the help,
Danny Bogner
Big Bear Ca

 

[Artisan]

Your going to torture yourself to death unless you grab those TM's and start reading.
Yes, it is a real bitch, espically if your challenged when it comes to reading but do it.

I do not have a CTIS system. I can not give you first hand knowledge but, the TM's
can help tremendously.

The best way to tackle the TM's is to Download ALL MANUALS pertenant to your truck.

PARTS
MAINTENANCE
FIELD MAINTENANCE
Operators Manual
Lubrication Orders
and others.

Start learning where things are. BUT, a good trick is to open a file and SEARCH
for a term. Case and point, I grabbed TM 9-2320-272-24-1 and did a quick
search for " CTIS " and on PDF page number 357 ( Section 2-267 ) I found
what appears to be the beginning of the CTIS troubleshooting area.

Go to the TM DL link on this board I gave you and download ALL MANUALS that are for the
M939 Series of Trucks. Your truck is an
M939 Series. There is no such thing as a "900" series FWIW.

PS, if you tightened something and all of a sudden something didn't work
troubleshoot what you just did. Take it apart, look at it all, is there a pin or socket
broken? Are all pins touching, do you need ot bend each pin just a smidge to
make them touch? Air blow out debris, look at everything hard looking for an
anomaly.

Do the lights go dead because the the headlight battle switch is in the off position?
Posistion 1 to the right makes blinkers and other stuff work.
Posistion 2 to the right turns on headlights and clearance lights.
etc.

 

[bogshotrods]

Your going to torture yourself to death unless you grab those TM's and start reading.
Yes, it is a real bitch, espically if your challenged when it comes to reading but do it.

I do not have a CTIS system. I can not give you first hand knowledge but, the TM's
can help tremendously.

The best way to tackle the TM's is to Download ALL MANUALS pertenant to your truck.

PARTS
MAINTENANCE
FIELD MAINTENANCE
Operators Manual
Lubrication Orders
and others.

Start learning where things are. BUT, a good trick is to open a file and SEARCH
for a term. Case and point, I grabbed TM 9-2320-272-24-1 and did a quick
search for " CTIS " and on PDF page number 357 ( Section 2-267 ) I found
what appears to be the beginning of the CTIS troubleshooting area.

Go to the TM DL link on this board I gave you and download ALL MANUALS that are for the
M939 Series of Trucks. Your truck is an
M939 Series. There is no such thing as a "900" series FWIW.

PS, if you tightened something and all of a sudden something didn't work
troubleshoot what you just did. Take it apart, look at it all, is there a pin or socket
broken? Are all pins touching, do you need ot bend each pin just a smidge to
make them touch? Air blow out debris, look at everything hard looking for an
anomaly.

Do the lights go dead because the the headlight battle switch is in the off position?
Posistion 1 to the right makes blinkers and other stuff work.
Posistion 2 to the right turns on headlights and clearance lights.
etc.

Thanks so much for the help, the message I received from Suprman about the light switch was SPOT ON. I just went out and started the truck up and when it was up to proper air pressure I turned on the head lights and BAM the HWY selector lit up, so I hit the XC selector and it aired down just like it's supposed to do, BUT the 1 light , where it be in HWY or XC still blinks, but then when I turn off the head lights out goes the light on the controller, oh well at least it's working and your right about not pulling my hair out over it, but this being my first adventure with this kind of Beast I'm a little out of my element, I'm a pretty good wrench most of the time, but I'm learning more and more from this every time I log in. I have a A 923A2 so will the 939 TM's help with the 923 ??

Thanks again,
Danny

 

[Artisan]

Danny go download the M939 series of tm's. Just grab one to start
and open it. Towards the very top it lists what trucks it serves.
Look for M923A2....

Ya just gotta do it...it is daunting yes, but once you spend
a few months looking these things over you will have somewhat
of a better understanding.

I still struggle w/ them but they can be a HUGE help.

 

[bogshotrods]

Got ya Suprman, a couple of MONTHS, oh boy hope we get some snow so I have time to brouse thru em, but it's not looking very good for a big snow day anytime soon