It's alive!!!

[Thunderbirds]

Well, it had to happen at some point... I believe my PCB box went out yesterday.

Without any previous symptoms, yesterday tried to start. Cranked for for 10 seconds, no start, filled the garage with white smoke. For some reason I even watched the trucks' voltmeter and no voltage drop or rise, even though the wait light came on for 7 seconds. Waited for 90 seconds and cranked again for 10 seconds, then a hesitant start. But much more white smoke. Ran into town, started up every time with the hot engine.

I believe my PCB gave up yesterday. This morning I went out and confirmed with a digital voltmeter, even with the wait light on for 7 seconds, no power to the plugs. Plugs are about 5 weeks old.

Is there any way to tell which version box I have just by looking at it from the outside? I know its one of the older, it doesn't have the diagnostic port.

I read posts for bypassing the plug controller, posts for DIY repairing, posts for others offering to repair, and then posts for upgrading to the newest box and TSU but that gets expensive.

What are the options that make the most sense, are there any more troubleshooting steps? I will get into the T/S part of the TM tonight, just thought to poke here first.

Thanks all.

 

[TOBASH]

Read my signature line for ways to fix and improve it.

Schematics are posted. Feel free to PM

 

[Thunderbirds]

Read my signature line for ways to fix and improve it.

Schematics are posted. Feel free to PM

I started on that thread a while back, but until I actually get into the box itself, most doesn't make sense in my noggen. I will be removing the box and opening in the next few days, maybe do some multimeter probing. I would reach out in the next few days via PM with tons of questions. Thanks for the offer!

There aren't too many other problems that could lead to this, could there be?

 

[Mogman]

I started on that thread a while back, but until I actually get into the box itself, most doesn't make sense in my noggen. I will be removing the box and opening in the next few days, maybe do some multimeter probing. I would reach out in the next few days via PM with tons of questions. Thanks for the offer!

There aren't too many other problems that could lead to this, could there be?

If you let the magic smoke out it will not be hard to find the problem, likely a FET or two with big holes it them, that is a really old box so its time was due.

 

[Thunderbirds]

If you let the magic smoke out it will not be hard to find the problem, likely a FET or two with big holes it them, that is a really old box so its time was due.

Depending on what happened, feasible to repair, bypass or replace is my guess?

 

[Thunderbirds]

Right now I am completely baffled and am asking for a sanity check. I have completely disconnected both batteries, all 4 terminals, and wanted to make sure all power is dissappated before I remove the PCB. To do that I flipped the start switch to run, and the brake light is on

What is happening? Where is this power coming from? Mind you, it's not a full 24V bright, but still very bright, even under the garage light very visible

 

[Mullaney]

Right now I am completely baffled and am asking for a sanity check. I have completely disconnected both batteries, all 4 terminals, and wanted to make sure all power is dissappated before I remove the PCB. To do that I flipped the start switch to run, and the brake light is on

What is happening? Where is this power coming from? Mind you, it's not a full 24V bright, but still very bright, even under the garage light very visibleView attachment 932169

.
So... About 12 hours later.
Is the light still on?

Even a "cap" would have drained itself by now.

.

 

[Thunderbirds]

.
So... About 12 hours later.
Is the light still on?

Even a "cap" would have drained itself by now.

.

I couldn't tell you, once I saw that I continued to remove the box for more T/S. As soon as I disconnected the under dash connector and tried the switch again, the light did not come back on. So I assumed it is a capacitor powering the system and not a "ghost" exciter. That gave me pause and I didn't break open the box for inspection, just because vehicle electronics are foreign to me and I hated the idea of discharging that via my body.

I then reinstalled and reconnected the box just to see if any wires were lose, but no-go. Still no voltage drop, the wait light comes on for the 7 seconds or so, much smoke during the first start of the day. Once the truck ran for just even a few minutes, it fires right up within one second so I know the other systems are working ok.

There are a few avenues one could go, I am not sure yet how I want to go ahead. Manual push button, Camo box, new KDSS.

Life is throwing me for a loop, so it may be a few weeks before I get back to troubleshooting and fixing. Still open to ideas or suggestions.

Thanks!

 

[Thunderbirds]

.
So... About 12 hours later.
Is the light still on?

Even a "cap" would have drained itself by now.

.

I couldn't tell you, once I saw that I continued to remove the box for more T/S. As soon as I disconnected the under dash connector and tried the switch again, the light did not come back on. So I assumed it is a capacitor powering the system and not a "ghost" exciter. That gave me pause and I didn't break open the box for inspection, just because vehicle electronics are foreign to me and I hated the idea of discharging that via my body.

I then reinstalled and reconnected the box just to see if any wires were lose, but no-go. Still no voltage drop, the wait light comes on for the 7 seconds or so, much smoke during the first start of the day. Once the truck ran for just even a few minutes, it fires right up within one second so I know the other systems are working ok.

There are a few avenues one could go, I am not sure yet how I want to go ahead. Manual push button, Camo box, new KDSS.

Life is throwing me for a loop, so it may be a few weeks before I get back to troubleshooting and fixing. Still open to ideas or suggestions.

Thanks!

 

[Mullaney]

I couldn't tell you, once I saw that I continued to remove the box for more T/S. As soon as I disconnected the under dash connector and tried the switch again, the light did not come back on. So I assumed it is a capacitor powering the system and not a "ghost" exciter. That gave me pause and I didn't break open the box for inspection, just because vehicle electronics are foreign to me and I hated the idea of discharging that via my body.

I then reinstalled and reconnected the box just to see if any wires were lose, but no-go. Still no voltage drop, the wait light comes on for the 7 seconds or so, much smoke during the first start of the day. Once the truck ran for just even a few minutes, it fires right up within one second so I know the other systems are working ok.

There are a few avenues one could go, I am not sure yet how I want to go ahead. Manual push button, Camo box, new KDSS.

Life is throwing me for a loop, so it may be a few weeks before I get back to troubleshooting and fixing. Still open to ideas or suggestions.

Thanks!

.
You may want to open the box and look at the "board" down in the bottom. It could be that a capacitor was "blown" off that board. Maybe. Maybe not, but definitely worth an investigative look...

 

[mow***com]

There are a few avenues one could go, I am not sure yet how I want to go ahead. Manual push button, Camo box, new KDSS.

Life is throwing me for a loop, so it may be a few weeks before I get back to troubleshooting and fixing. Still open to ideas or suggestions.

Thanks!

I remember being at this crossroad with my M1123 and chose to just use a new KDS smart start.
Back when I worked on little Mitsubishi Mighty Max/Dodge Ram50 trucks.... The 2.3 turbo diesel had a voltage reduction glow plug system at 12/6 volts.
I can't recall if I was missing a few things, or wanted simplicity. But, remember bypassing it and just wiring a momentary switch to a solenoid, powering the glowplugs. In the 5+ years that I owned it, I can't remember a single problem with it.
You just have to be smart enough not to hold your switch for too long.

I never favored the idea of having two sets of glow plug wires in the engine bay. That is the only way I have seen it done in a HMMWV, due to the box.

 

[Thunderbirds]

I started on that thread a while back, but until I actually get into the box itself, most doesn't make sense in my noggen. I will be removing the box and opening in the next few days, maybe do some multimeter probing. I would reach out in the next few days via PM with tons of questions. Thanks for the offer!

There aren't too many other problems that could lead to this, could there be?

Hey all,

just to pick up where I left off a few weeks ago, my symptoms are Glowplugs are not being fired. Wait light comes on for 5-6 seconds, hard start now that the temperatures dropped from the 90s to the 60s and 70s, lots of smoke, no voltage drop when turning to run during the wait light period, no audible clicking, no voltage to the glowplugs.

I finally put life to the side and opened the box this morning (couldn't sleep, it is full moon or just shortly after) and it IS NOT what I expected to see. I've done a little research, but have not come by the innards of this sort:





Question, what model box is this, where do I go from here to T/S and start fixes? I was expecting solenoids, bunch of wiring, corrosion and maybe even Jason from Halloween or Freddy. I am not good with fine electrics to begin with. This is the temp sensor installed:



Thanks in advance.

 

[Thunderbirds]

I've been able to find some more info on this EESS box. It seems to be Prestolite or Ametek with P/N 12446779. It also seems the TSU is correct for htis box.

What are the chances this can be fixed? Does anyone have a step by step guide? I see no burn marks or other obvious damage:

 

[Retiredwarhorses]

I've been able to find some more info on this EESS box. It seems to be Prestolite or Ametek with P/N 12446779. It also seems the TSU is correct for htis box.

What are the chances this can be fixed? Does anyone have a step by step guide? I see no burn marks or other obvious damage:

View attachment 933597

that’s a PCB with a GPC….toss it in the garbage can

 

[Thunderbirds]

that’s a PCB with a GPC….toss it in the garbage can

.
Good advice, been thinking in along those lines. Thanks. Besides the newest ESSS, which is most reliable in your opinion? Any model stand out over others?

I appreciate all info and opinions.

EDIT:
'Been considering the manual boxes talked about by many members here, but would like to stay automatic if the box is reliable enough.

 

[ikoinu]

TLDR: Wire up a momentary button in the cab to a 24v relay, purchase a HMMWV glow plug harness and replace the current factory harness (just tie the old connectors out of the way), and push the button when you need glow plugs.

The manual temporary button for controlling glow plugs is a good way to go. And the cheapest.

Manual Glow Plug Control Instructions

Manual Glow Plug Controller Walkthrough I'm making this as I have time, so please bear with me. ;-) I will be marking the pictures and updating them, along with a list of parts & a step-by-step. Parts: Ebay Parts: HMMWV Glow Plug Distribution Box Interface Harness P/N: 12379865 $42.50 24V...

www.steelsoldiers.com

I'm not against going for a new style or hardened smart box in the future, but following the KISS principle is usually the most reliable.
I do understand wanting to keep everything 'factory' though.

(Note: I never completed that instruction post, will have to get back to it)

 

[TOBASH]

Hey all,

just to pick up where I left off a few weeks ago, my symptoms are Glowplugs are not being fired. Wait light comes on for 5-6 seconds, hard start now that the temperatures dropped from the 90s to the 60s and 70s, lots of smoke, no voltage drop when turning to run during the wait light period, no audible clicking, no voltage to the glowplugs.

I finally put life to the side and opened the box this morning (couldn't sleep, it is full moon or just shortly after) and it IS NOT what I expected to see. I've done a little research, but have not come by the innards of this sort:

View attachment 933595



Question, what model box is this, where do I go from here to T/S and start fixes? I was expecting solenoids, bunch of wiring, corrosion and maybe even Jason from Halloween or Freddy. I am not good with fine electrics to begin with. This is the temp sensor installed:

View attachment 933596

Thanks in advance.

I could be wrong but here goes… Looks to me like an SSI solid state.

Not a fan. I won’t accept on trade-ins.

They can be worked on BUT you need to purchase lots of wires and solder and two solenoids. Essentially only the plugs are salvageable.

 

[Thunderbirds]

I could be wrong but here goes… Looks to me like an SSI solid state.

Not a fan. I won’t accept on trade-ins.

They can be worked on BUT you need to purchase lots of wires and solder and two solenoids. Essentially only the plugs are salvageable.

.
That is great info, thanks good Sir. I was able to purchase a used, but guaranteed working S3 unit with matching TSU. When it gets here and I am able to test, I’ll post about it.

TLDR: Wire up a momentary button in the cab to a 24v relay, purchase a HMMWV glow plug harness and replace the current factory harness (just tie the old connectors out of the way), and push the button when you need glow plugs.

The manual temporary button for controlling glow plugs is a good way to go. And the cheapest.

Manual Glow Plug Control Instructions

Manual Glow Plug Controller Walkthrough I'm making this as I have time, so please bear with me. ;-) I will be marking the pictures and updating them, along with a list of parts & a step-by-step. Parts: Ebay Parts: HMMWV Glow Plug Distribution Box Interface Harness P/N: 12379865 $42.50 24V...

www.steelsoldiers.com

I'm not against going for a new style or hardened smart box in the future, but following the KISS principle is usually the most reliable.
I do understand wanting to keep everything 'factory' though.

(Note: I never completed that instruction post, will have to get back to it)

I will review the instructions and maybe build a spare unit. Thanks for the post.

 

[Thunderbirds]

I got my used, new to me S3 box and new TSU. Installed them and they worked like designed. Turned to run, voltage dropped upon plug light coming on, raised upon light turning off, and stared immediately whilst 55 degrees in the garage. Last time I started it, it took a good 10-15 seconds and flooded the garage with white smoke. Man, what a good day, small victories.

 

[Thunderbirds]

Little update on a minor disaster averted (not by me but by luck). While out and about last weekend ( https://www.steelsoldiers.com/threads/out-and-about-with-my-hmmwv.201914/post-2588544 ), and back home we noticed a leak of clean and clear fluid, that did not have a diesel smell, dripping from the passenger side of the engine, but also splattered about a 2 square foot radius from the brakes on that side. I had assumed the brakes or brake lines were damaged during rock crawling, brake fluid was my guess since that is the only fluid that is clear.

This morning I planned on taking the truck to pressure wash and find the source. But before we left I got underneath one more time. That is when I noticed the fluids dripping from the front right engine mount bracket, it was a steady drip every 10 seconds. But this time I also noticed a diesel smell to the fluid. It turns out the most forward passenger fuel injector was 1/3 turn lose and let it drip. Once tightened the drip immediately stopped. That gave me courage to take it to town and get pressure washed. I did the entire truck. We drove another 30 miles, every few miles stopping and inspecting the under-body area. Happy to say there is absolutely no sign of any leakage anymore on the entire truck. I am beyond happy I am not forced to chase gremlins and spend big $$$ on parts.

Begs one question, is there a torque value to the injector, or is it the very calibrated German gut-und-tight?