LMTV CTIS Question

[Hobie_rat]

This switch box is for Troubleshooting CTI system issues only it is not intended for vehicle operation.
* * * MY DISCLAIMER * * * Note that inflating and deflating past the normal software values will cause the system to malfunction and could be Dangerous!

Follow the 2018 CTIS Troubleshooting Guide for connections.
View attachment 747430

I have a question. My ‘96 1078’s ctis seems to operate ok except the hwy switch doesn’t activate and light up. It do when I bought the truck 3weeks ago. Now it doesn’t. No threads talk about this situation. Any ideas

 

[Third From Texas]

I have a question. My ‘96 1078’s ctis seems to operate ok except the hwy switch doesn’t activate and light up. It do when I bought the truck 3weeks ago. Now it doesn’t. No threads talk about this situation. Any ideas

First guess would be a bad controller.

The valves, etc are all used in the various modes. If only one mode is out and the others function, I'd say the controller is fubar.

You have options:
1) Replace with used (keep in mind these things all fail at a certain point like the one you have and even used are not typically cheap)
2) Replace with NOS (expensive and I mean REALLY expensive and at some point, they all fail)
3) Replace with manual (several members here have done this, no computer to fail, it's inexpensive, and not difficult to convert)
4) Replace with another controller type (several users are running Arduino controllers, a tiny project computer assembled and programmed for the same task as the OEM)

You can find all of these solutions here on SS. No shortage of used or new. The manual setups are well documented in a couple threads here. And Christian here sells Arduinos that are plug-m-play.

Also keep in mind there are a couple versions so be certain what you buy will work with your A0 truck.

 

[Hobie_rat]

First guess would be a bad controller.

The valves, etc are all used in the various modes. If only one mode is out and the others function, I'd say the controller is fubar.

You have options:
1) Replace with used (keep in mind these things all fail at a certain point like the one you have and even used are not typically cheap)
2) Replace with NOS (expensive and I mean REALLY expensive and at some point, they all fail)
3) Replace with manual (several members here have done this, no computer to fail, it's inexpensive, and not difficult to convert)
4) Replace with another controller type (several users are running Arduino controllers, a tiny project computer assembled and programmed for the same task as the OEM)

You can find all of these solutions here on SS. No shortage of used or new. The manual setups are well documented in a couple threads here. And Christian here sells Arduinos that are plug-m-play.

Also keep in mind there are a couple versions so be certain what you buy will work with your A0 truck.

thank you

 

[Mullaney]

thank you

.
If you want parts or testing of your existing controller, @Suprman is a good point of contact. I have bought several things from him over the years - and he has been helpful and reasonably priced...

 

[Ronmar]

Yea bad controller or keyboard. What pressure are the tires at now. I dont recall from when I gutted mine wether the keyboard is replaceable. You can unscrew the keyboard cover from the top and access the keyboard and see if it has a connection that is accessable. I would look at that before I condemn it…

 

[coachgeo]

with truck off... unplug it.... remove it. dissasemble it as far as your comfortable...... clean the shiat out of it with CRC or some other electronics cleaner....... do some light brushing with a soft tooth brush, etc. Dont forget to clean the pins and pin holes in the connector with tiny tiny brush or??? Can't hurt and only cost you 8-10 bucks or less and that is with the cost of tooth brush lol

think this is a replacement keypad. Tom Bauer* makes?/sells these is a member here

FMTV LMTV M1078 New CTIS Keypad, Spicer, replace your worn or broken keypad | eBay

Make your CTIS look new again.

www.ebay.com

* https://www.lmtvtrucks.com/

 

[Hobie_rat]

Yea bad controller or keyboard. What pressure are the tires at now. I dont recall from when I gutted mine wether the keyboard is replaceable. You can unscrew the keyboard cover from the top and access the keyboard and see if it has a connection that is accessable. I would look at that before I condemn it…

Thanks for the responses. The tires are currently at 35 psi. I removed the back of the unit and it incased in clear silicon? So close and yet, so far. And I was looking at that key pad you mentioned. It’s just a new , “pretty, pretty” as my Dad used to say It’s only a replacement cover when the old one cracks. No access to the guts. At least not mine. Philip from Dana/Spencer said if everything works but high way mode it’s probably toast. And like someone said “they ain’t cheap”

 

[Hobie_rat]

.
If you want parts or testing of your existing controller, @Suprman is a good point of contact. I have bought several things from him over the years - and he has been helpful and reasonably priced...

I would be interested in seeing what can be done or a replacement part

 

[Ronmar]

Yea the whole unit is potted horribly, no internal box access. I couldn’t remember if the keyboard had any access. I gutted my dead one to make my first manual controller prottype.

 

[Hobie_rat]

Yea the whole unit is potted horribly, no internal box access. I couldn’t remember if the keyboard had any access. I gutted my dead one to make my first manual controller prottype.

Ya the guy fromDana walked me through trying to bypass the hwy button but, no joy. The controller is burnt. Time for a new one

 

[coachgeo]

Ya the guy fromDana walked me through trying to bypass the hwy button but, no joy. The controller is burnt. Time for a new one

did you jump your truck recently? Or weld on it recently?

 

[Hobie_rat]

did you jump your truck recently? Or weld on it recently?

It was jumped through the nato charging point the day it was released to me. But not since 4 new batteries all charged independently before installing them in the box. It worked….and now it doesn’t

 

[Mullaney]

It was jumped through the nato charging point the day it was released to me. But not since 4 new batteries all charged independently before installing them in the box. It worked….and now it doesn’t

.
Just because... Why don't you use a multi-meter and measure all four batteries? No need to disconnect anything. Just meter plus and minus on each battery. Possibly record those measurements here if you would.

These trucks are notoriously "over batteried" and under charged. Strange things happen where one of the batteries in the 12v string will get low and the truck acts spastic. Cheap thing to look at...

 

[Third From Texas]

Honestly, I think these controllers are extremely easy to fry. It's why I'll be looking to an alternative to replace mine.

 

[Hobie_rat]

.
Just because... Why don't you use a multi-meter and measure all four batteries? No need to disconnect anything. Just meter plus and minus on each battery. Possibly record those measurements here if you would.

These trucks are notoriously "over batteried" and under charged. Strange things happen where one of the batteries in the 12v string will get low and the truck acts spastic. Cheap thing to look at...

I haven’t put a meter on them since I installed 4 new batteries. At least one had a dead short. I figure this is why it wouldn’t jump start. One video I saw explained how the zig zag looming of the 12 v line is not optional for charging

 

[Hobie_rat]

Honestly, I think these controllers are extremely easy to fry. It's why I'll be looking to an alternative to replace mine.

You would think they would have made them more robust

 

[Hobie_rat]

I haven’t put a meter on them since I installed 4 new batteries. At least one had a dead short. I figure this is why it wouldn’t jump start. One video I saw explained how the zig zag looming of the 12 v line is not optional for charging

To date since I installed the new batteries, I’ve had no issues aside from the one problem with the ctis

 

[Hobie_rat]

.
Just because... Why don't you use a multi-meter and measure all four batteries? No need to disconnect anything. Just meter plus and minus on each battery. Possibly record those measurements here if you would.

These trucks are notoriously "over batteried" and under charged. Strange things happen where one of the batteries in the 12v string will get low and the truck acts spastic. Cheap thing to look at...

I’ll get those voltages in a min

 

[Awesomeness]

You would think they would have made them more robust

Realistically, they probably aren't very easy to kill. Military electronics have to meet extremely rigorous specifications (e.g. temp, overvoltage, polarity, EMP, EMI, etc.). But we have a member ( @Stellaevil who I haven't seen in a while), that worked at Spicer, and said that there are capacitors(?) inside that fail after many years, and the potting makes them irreparable. Repairability just wasn't something the government cared about, compared to being vibration and water proof.

 

[Hobie_rat]

I’ll get those voltages in a min

Here are the current readings from all 4 batteries with the engine on and off