CTIS keypad

good idea. you just have to heat it just enough to not melt the components off

I don't think resign-based potting will "melt off" inverted on an oven rack. It will "gel" at it's "liquidation" point, but not "flow".

Any increase in heat beyond that would simply start to burn things...

Third From Texas said:

I don't think resign-based potting will "melt off" inverted on an oven rack. It will "gel" at it's "liquidation" point, but not "flow".

Any increase in heat beyond that would simply start to burn things...

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OK

Well, regardless
I have some first pictures of what the ECU looks like without the potting.

Looking it over quickly I saw a diode that doesn't seem too happy.

So you know while you are in there poking around, I tore the dead one I had open to see if the diagnostic pins on the amphenol were wired. They weren't in my example, which is too bad because the software to program / diagnose them seemed to be obtainable from eaton. Are they wired on yours? I can lookup the pinout tomorrow if you don't have it.

Yeah, get the pinout . Won't hurt to have it here.

319cssb said:

Yeah, get the pinout . Won't hurt to have it here.

Click to expand...

a,N,D,A are the diagnostic busses.

If you PM me your email I can send you the technical material.

Here is what the underside looks like

this is a close-up of the solder connection on the main board

And here is a close-up of the solder points on the connector

This is what the plug looks like (pardon the silicone remnants in the connector. I will throw the thing in the ultrasonic cleaner later.

All pins seem to be connected and also connected on the main PCB. So I assume that the diagnostic will work.

319cssb said:

This is what the plug looks like (pardon the silicone remnants in the connector. I will throw the thing in the ultrasonic cleaner later.
View attachment 747899
All pins seem to be connected and also connected on the main PCB. So I assume that the diagnostic will work.

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That's really interesting, thanks for checking that out. As I was saying they were not wired on the old unit I had, but it may be that they started wiring them on the newer units (I suspect from the 5-ton). Since I have a NOS unit, it will be worthwhile for me to hook up an interface and see if I can get the software going. I'd like to reprogram my pressures.

a,N is J1808A/B and D,A is J1939+/- respectively. The software to interface / program the units is the "dana diagnostic tool" which was available for free the last time I checked.

Mine was for a A1 truck, So I imagine they implemented that for these units.

Yes the DDT is free, but you need a dearborn adaptor for it.

Then you can change tire pressure setting, interval of how many times the ECU checks the pressure, and above all can do diagnostics.
As i have done here

Turns out the capacitors used are General Purpose Nichicon. I will get some new Low impedance capacitors . I'll got 20% above Voltage rating, so they should last longer.
two 47uF 200V (original was 47uF 160V).
and one 1000uF 16V (original 1000uF 10v)

I decide to use higher voltage ratings and low impedance for better results.
All of these Capacitors tested too low in capacitance. The 1000uF only had 945uF.

Thats a likely cause of failure, so if you can get the ECU De-potted and have some soldering skills then it's a cheap fix.
Would be nice if M35 would tell us what his findings were, but it's unlikely to happen.

Once I have the ECU verified working again. I'll show you guys how to replace the Dome switches with Tactile Micro switches

Why is it unlikely to happen? It is not rocket science, you just pick away at it and try various solvents and heat. I have unpotted hundreds of parts to repair or reverse engineer.

I have new membrane switch cover parts for sale soon, maybe later next week. Most parts have already been made.
Comes with all the pieces you will need including the 5 dome switch parts.

We were asking about what this easy to find part was that you replaced.
Its been posted here already by me of how to remove the potting. But you said these units are easy to repair, but you didn't share with the group what you did to remedy the problem.

Well as I guess you know any electronics can be repaired, just find the failed part or parts or failed solder joints etc. I make a very good living doing that.
No I have not repaired a CTIS yet. But that is because I have not been able to get my hands on a bad one.

m-35tom said:

I have new membrane switch cover parts for sale soon, maybe later next week. Most parts have already been made.
Comes with all the pieces you will need including the 5 dome switch parts.
View attachment 749026

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I guess you have to keep them in the stock pattern for the mil-spec guys, but if it were me I would rotate the labeling 90° to the left so it can be seen at a glance by the crew (not that most won't know by the position, but still if I redo anything on my truck I'm doing it better than mil-spec personally).

no

m-35tom said:

Well as I guess you know any electronics can be repaired, just find the failed part or parts or failed solder joints etc. I make a very good living doing that.
No I have not repaired a CTIS yet. But that is because I have not been able to get my hands on a bad one.

Click to expand...

I read that wrong, i thought you said you fix ctis ECU's on a regular basis
no problem then.