Test/Rebuild of KDS CR2699 PCB

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Re: Test/Rebuild of KDS CR2699 PCB

Post by Augi » Fri Mar 25, 2016 10:18 pm

Check out Oshpark for cheap PCB's. That's where I get mine done.

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Fenris

Re: Test/Rebuild of KDS CR2699 PCB

Post by Fenris » Sat Mar 26, 2016 4:13 pm

Ok you people on this forum have driven my curiosity to beyond insanity here. Enough to do some very detailed research. What has brought up some questions...

First question, there was a Protective Control Box that was recalled a number of years back that had 2 engine harnesses (one for running the glow plugs, the other for the rest of the engine) and it used this harness (item 12379865) https://www.real4wd.com/zedSuite/catalo ... o=12379865, what was the model of that PCB? I know this box was recalled cause it caused trucks to start up out of nowhere and even set a few on fire. And another question is, what was the part number to the other engine harness that would plug into that box (like it would feed the alternator, starter motor, etc..) (preferably for the 6.2 L engine)?

One day I went to sleep, I had a dream of designing my own control box, and remembered the story of this model. So I said "I know I can design one better, one that works and wont set my truck on fire". Why I like that one over the regular engine harnesses is, I can make a microcontroller test the resistances of each glow plug individually and have the box tell me which glow plugs are dead or not working right up front when you turn the ignition key with say blink codes of the Wait to Start light, or use a beep code pattern.

Now before I can ask my next question, I have to share what I have learned so people know what I am asking for properly. The old PCB boxes made by Prestolite that drive everyone crazy cause they pulse the voltage gauges all over the place. Why they do this is quite cool actually (at least to me anyway), is because there are 3 switches and 2 resistive heaters in that little glow plug module.
  • Pin 1: Feeds the after glow heater of 130 ohms (at 27-28 volts from alternator voltage) which causes the after glow switch to open at 160 degrees F
  • Pin 2: This lead has no connection
  • Pin 3: This is your feed back line which triggers the solenoid that energizes or de-energizes the glow plugs
  • Pin 4: This is your main glow plug heater of 27 ohms (at 23-25 volts from battery voltage) which causes the main glow plug switch to open at 180 degrees F
  • Pin 5: This is your ground lead that provides ground to the heating resistors at Pins 1 and 4
  • Pin 6: This is your power feed that provides the feed back current down Pin 3 used to trigger the glow plug solenoid and gets its power off the line needed to keep your injector pump going while your engine is running
Now how this is suppose to work is, artificial heat is being generated under the heat controlled glow plug switches inside the glow plug controller. Which also takes the heat of the engine coolant into it's effect in order to generate a time duration ratio used to keep the glow plugs active for just the right amount of time. That allows the surrounding weather temperature and the temperature of the engine (weather its been turned on/off recently) to take in effect how long each glow cycle should be set at.

The reason why you see your voltage gauge bounce all over the place causing the loaded down pulses, is the after glow switch keeps going on/off all over the place to get your engine all up to it's peak operating temperature as genitally as possible. This would be the reason why you would see it pulse like crazy for a long time in an Alaska winter and almost never in a California sunny sumer. All of which can be eliminated by feeding the feed back line through a microcontroller to control after glow pulses (should they even be necessary) more genitally and save the strain on your poor glow plugs therefore extending there life.

I know what your saying, "this is all nice to know but what is your question?" Say you upgraded your control box to S3 and you install that glow plug controller with the yellow band on it inside your engine. I know it doesn't operate in the same way as the older Prestolite version. So my question is, how does it work in detail? Is it digital like I hear people saying it is? Or is it analog like the older version but perhaps with different resistive heaters inside for less current consumption making it easier for the circuitry to control it better? I want to know how it works. If I am to design my own box that can do more then the S3 for much less, I need to know how this glow plug controller operates. I know it's better, but I don't know why or how. Is there anyone that can give me details on this? Has anyone ever bothered to connect measuring equipment to it themselves to see how it actually behaves?

By making my own box (I know I have mentioned this before), I could do things like adding command start features with key chain remotes, anti-theft and GPS location controls, getting status on dead or disconnected glow plugs, engine operation diagnostics (as to heat operation levels, hours of operation which can be used to automatically inform users when to change oil as a convenient reminder), and possible other idea's I haven't thought of yet all jammed packed into one water tight box as a complete kit. And none of these features will ever surface in future designed options as far as PCB boxes go. None of that seems overly difficult to do considering much of the needed functions all come in from 2 plugs...

Engine Harness
  • Pin A: (output) Feeds fuel injector solenoid, Pin 6 of glow plug controller, Fan temperature switch, Time delay/Engine clutch solenoid
  • Pin B: (input) Pin 3 of glow plug controller (temperature switching feed back)
  • Pin C: (output) Pin 4 of glow plug controller (glow plug heating/timing resistor element)
  • Pin D: (output) Feeds all 8 glow plugs (8 gauge wire required, expected 150 amps)
  • Pin E: (input) Positive battery terminal feed coming off of the starter motor (8 gauge wire required)
  • Pin F: (Bi-directional) Connected to alternator, Sense of alternator, Transmission kick down switch, Cold advance switch (also needed to excite alternator at engine start-up) (8 gauge wire required)
  • Pin G: (input) Alternator A.C. Tap
  • Pin H: (output) Pin 1 of glow plug controller (after glow plug heating/timing resistor element)
  • Pin I: (output) Starter motor starting line
Body Harness:
  • Pin A: (input) Engine start key turned
  • Pin B: (input) Run ignition
  • Pin C: (input) E-Brake warning (break on/off)
  • Pin D: Ground
  • Pin E: (output) Wait to start light
  • Pin F: (output) Power feed to all turn signal, head lights, and horn (connected directly to battery feed on engine harness pin E)
  • Pin G: (output) Power feed to the ignition key switch (connected directly to battery feed on engine harness pin E)
  • Pin H: (output) Power feed to internal cab heating fan (active when run ignition is live)

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Re: Test/Rebuild of KDS CR2699 PCB

Post by Retired War Horses » Sun Mar 27, 2016 6:47 am

After glow was only present on the KDS and Nartron EESS, and perhaps the short lived green label as well. This was an emissions thing I am told, I say this because the civ H1's do the same...I know my 98 does, but not for nearly as long as first Gen EESS boxes. The length of time for after glow Has never varied based on temp, contrary to popular belief...it's gets freaking cold in California...it's not uncommon to hit 25deg at my place in the winter, not as cold as Alaska, but still below freezing and my trucks fire up...it's my 98 hummer that craps all over it self, all my HMMWV's start fine.
The after glow went away in the S3 box....all in all, a better box.
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Re: Test/Rebuild of KDS CR2699 PCB

Post by Fenris » Sun Mar 27, 2016 10:04 am

That is weird, because I have the old Prestolite PCB in pieces all over my desk right now (NSN: 6110-01-395-9585). Manly because it failed on me and wont start my truck up anymore. I have found a dead solenoid in it, which I hope is the problem cause I'm not looking forward to rebuilding the circuit board because the components are rather pricey. However by taking it apart I have had a chance to look at it very closely, the return line goes right goes right to the glow plug solenoid from the glow plug controller, and this PCB makes my glow plugs and voltage gauge pulse all over the place.

For the H1's maybe that makes sense, they have alot more computers inside them that control all kinds of functions which make things comfortable for the people inside. But to say that it's emissions on a HMMWV, it doesn't electrically make sense. There is not a single sensor to be found on my truck that taps into the emissions. It's just striate pipe from the exhaust manifolds, to the muffler, then out the deep fording exhaust pipe that goes way up into the air off the back end of the truck. Also, how can it not be based on temperature when it has the details right on the electrical diagram of the M996-997 HMMWV? That manual covers the insides of the glow plug controller in detail, it has heating switches all over the inside. Even The Diesel Page technical manual for the 6.2L/6.5L civilian trucks go over the glow plug connections in great detail, it's just wired slightly different then the HMMWV which higher resistance values to control current better at 12 volts rather then 24. I'm thinking that perhaps your truck just happens to be less sensitive to environmental change then of some other peoples.

Since your here, you seem to know a lot of things about...a lot of things....do you know what part number the control box that had the 2 engine harnesses (the one that was recalled for setting trucks on fire) was called? I was looking for the details on it and all the harness parts.

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Re: Test/Rebuild of KDS CR2699 PCB

Post by Retired War Horses » Sun Mar 27, 2016 11:30 am

I don't know the part number, and would never use one....also, the PCB is a POS, it requires a glow plug controller in the water crossover, those had issues all by themselves and a high fail rate...this is now a temp sending unit, the glow plug control function was moved into the EESS.
EESS and PCB are 2 different animals....if your not running a yellow label EESS with yellow banded TSU or an S3 EESS...your going to have issues.
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Re: Test/Rebuild of KDS CR2699 PCB

Post by Ted Gates » Sun Mar 27, 2016 11:35 am

This is a post I did on ss.

Attention new m998/hmmwv owners:
I thought I remind new owners that as mentioned in this sticky, there is a control box and harness you do NOT want to use. The control box and harness is made by LAU and the harness is 6110-01-446-7124, #12379865. I have seen them for sale on e-a- and they should be avoided.


I have one of these new with separate harness.

Fenris

Re: Test/Rebuild of KDS CR2699 PCB

Post by Fenris » Sun Mar 27, 2016 11:45 am

Retired War Horses wrote:I don't know the part number, and would never use one....also, the PCB is a POS, it requires a glow plug controller in the water crossover, those had issues all by themselves and a high fail rate...this is now a temp sending unit, the glow plug control function was moved into the EESS.
EESS and PCB are 2 different animals....if your not running a yellow label EESS with yellow banded TSU or an S3 EESS...your going to have issues.
I agree with you 100%, the PCB is a POS, but it's cheap to fix (at least it seems, $53 solenoid vs $620 S3 box). Do you know how the yellow banded TSU works electrically by any chance? Do you happen to know what signals are going to the box off the pins 1, 3 and 4 of the TSU?

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Re: Test/Rebuild of KDS CR2699 PCB

Post by Retired War Horses » Sun Mar 27, 2016 12:41 pm

I don't, but I don't want a box that is notorious for grenading all by glow plugs in 1 fell swoop.
It's not just the box that's the main issue, it is/was the glow plug controller in the water crossover.
So you can make the box work all day...but that GPC is the bigger issue. There are a few things I don't go cheap on...one is the ability for my truck to fail to start when I need it. So I don't mind spending the money on peace of mind.
Plus, I don't pay that much mine anyway...they do come up from time to time for hundreds less...you just have to be patient.
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Re: Test/Rebuild of KDS CR2699 PCB

Post by Action » Sun Mar 27, 2016 1:26 pm

speaking of TSU and GPC. I have the KDS white label smart start box. It is supposed to have a certain piece on the water tube, but the box works exactly the same with it unplugged. I haven't tried with a hot engine yet.

Jason

Fenris

Re: Test/Rebuild of KDS CR2699 PCB

Post by Fenris » Sun Mar 27, 2016 2:00 pm

Retired War Horses wrote:I don't, but I don't want a box that is notorious for grenading all by glow plugs in 1 fell swoop.
It's not just the box that's the main issue, it is/was the glow plug controller in the water crossover.
So you can make the box work all day...but that GPC is the bigger issue. There are a few things I don't go cheap on...one is the ability for my truck to fail to start when I need it. So I don't mind spending the money on peace of mind.
Plus, I don't pay that much mine anyway...they do come up from time to time for hundreds less...you just have to be patient.
I understand what your saying, unfortunately, I was forced into a situation where I am actually back in school (you know it is sometimes, education output = no money input) so I am forced into patching things up till a replacement crosses my path. Until then my truck is completely dead till I can drop in a new relay in this old POS and make my truck work again.

Also the reason why I was interested in the details of the old box that you clam can destroy glow plugs, is that I am in the process of designing a new box right now. I won't be able to buy the parts to build it, but designing it all on software is free at least for the time being. The TSU looks simpler, and if I knew how it worked, then I don't have to worry about the old GPC (all I really need out of it is a temperature feed back on/off the rest can be timed by a computer so it doesn't really matter all that much). But if anyone can get me the details of how the new yellow band TSU works, great, because all I know is that there is +24 volts on pin 6, and pin 5 goes to ground, so all that is left is pin 1,3 and 4.

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Re: Test/Rebuild of KDS CR2699 PCB

Post by linhster » Sat May 19, 2018 5:27 am

Fenris,

Did you ever find the information about the yellow band GPC? Please share if you have.


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