HMMWV Won't Start - Even after the usual suspects have been repaired......

[WalterMitty]

I know these not starting threads are popping up like bunny rabbits, but I'm at the end of my rope with this issue.The truck seems to start right up, and run fine in warm weather. However, it just won't start in cold weather. The WTS light has only worked maybe 2-3 times and when it did, the truck would usually start right up. But the typical issue is the dreaded WTS "flicker" and then you can crank for days and she won't turn over if it's cold outside.Here's what I've replaced so far: New Control Box, New TSU, New Glow Plugs. Installed grounding harness, replaced ignition switch. The WTS light still isn't working properly.I should add that will all the attempted starting, I've had to have the starter repaired 3 times, and now the batteries are low and will be replaced as well. I really do like the truck, but since I'm near Chicago, so far it's only been a reliable vehicle from June to about Sep. Help!

 

[TOBASH]

As a stop gap measure, did you consider adding a block heater? (Either that or a Webasto).That might keep you warm enough to start.

Otherwise I feel your frustration.

Good luck,

T

 

[DainGerous]

In what order did you do repairs? Out of sequence or not all done at same time will short out your components. Test voltage at glow plugs to see if they are getting current. There are also 2 fuses behind dash. Fuse 2 (top) controls dash lights plus works with EESS/glowplugs. You always need a spare TSU, EESS, fuse, and set of glowplugs with the truck. You might need to replace everything as it may have burned out. Voltmeter check and see if you're getting power. Go from there.

 

[NDT]

If you're not getting a solid long glow with the accompanying long voltmeter dips, none of your start problems should come as a surprise.

 

[WalterMitty]

In what order did you do repairs? Out of sequence or not all done at same time will short out your components. Test voltage at glow plugs to see if they are getting current. There are also 2 fuses behind dash. Fuse 2 (top) controls dash lights plus works with EESS/glowplugs. You always need a spare TSU, EESS, fuse, and set of glowplugs with the truck. You might need to replace everything as it may have burned out. Voltmeter check and see if you're getting power. Go from there.

Control Box, TSU, and Glow Plugs were all replaced at the same time. Still had the issue. After this, I replaced the TSU, Glow Plugs and installed the ground harness, and the ignition switch. The other issue is that I'm having another party do the work, as I am a mechanical midget. Thanks for the heads up on the fuse, and I will ask the mechanic to do the voltmeter check.

 

[WalterMitty]

If you're not getting a solid long glow with the accompanying long voltmeter dips, none of your start problems should come as a surprise.

The only surprise I'm getting is that I'm not getting a solid long glow even after all the new components.

 

[NDT]

Try to find a 63B light wheeled mechanic near you. A typical ASE mechanic will have no clue. The glow plug system HAS to work, when it does the engine will crank up immediately. I don't think your issue will be simple to solve via this website, I could be wrong.

 

[dmetalmiki]

Try to find a 63B light wheeled mechanic near you. A typical ASE mechanic will have no clue. The glow plug system HAS to work, when it does the engine will crank up immediately. I don't think your issue will be simple to solve via this website, I could be wrong.

Sound advice. So now do it (the once) And have it done it right. Post up the resolution of the fault. (for others to follow with same problem).

 

[Action]

The mechanic likely didn't unhook the batteries before parts replacing. Or even know where they are.

 

[Retiredwarhorses]

I know these not starting threads are popping up like bunny rabbits, but I'm at the end of my rope with this issue.The truck seems to start right up, and run fine in warm weather. However, it just won't start in cold weather. The WTS light has only worked maybe 2-3 times and when it did, the truck would usually start right up. But the typical issue is the dreaded WTS "flicker" and then you can crank for days and she won't turn over if it's cold outside.Here's what I've replaced so far: New Control Box, New TSU, New Glow Plugs. Installed grounding harness, replaced ignition switch. The WTS light still isn't working properly.I should add that will all the attempted starting, I've had to have the starter repaired 3 times, and now the batteries are low and will be replaced as well. I really do like the truck, but since I'm near Chicago, so far it's only been a reliable vehicle from June to about Sep. Help!

You haven't replaced the engine harness yet...I highly suggest you.

 

[frank8003]

What!?
You haven't replaced the engine harness yet...I highly suggest you.

 

[WalterMitty]

Well....he found the culprit. See pics below of inside the control box. This was aledgedly a new box from a previous repair. I have a few questions...

1). What is the likely cause of this getting fried out?
2). Is this repairable? Like trying 2 new transistors? Or is a new box needed?


Also, on the mechanic front, I think I have a guy I trust. He's a full time diesel mechanic and also maintains a Deuce in the fleet. He's the second guy I've gone to, and he's a good guy and trying to help me.

 

[WalterMitty]

Is this the correct wiring harness?

 

[3jacks]

Eriksmilitarysurplus.com has that same harness for $250

 

[86humv]

low, or bad batteries and also a Gen. that puts out to much voltage can cause issues also to your S3 box, or any other EESS box.

 

[Retiredwarhorses]

Well....he found the culprit. See pics below of inside the control box. This was aledgedly a new box from a previous repair. I have a few questions...

1). What is the likely cause of this getting fried out?
2). Is this repairable? Like trying 2 new transistors? Or is a new box needed?


Also, on the mechanic front, I think I have a guy I trust. He's a full time diesel mechanic and also maintains a Deuce in the fleet. He's the second guy I've gone to, and he's a good guy and trying to help me.

yes, that's the culprit...but now, what caused it? That's the million dollar question. Did you have a brand new in the box S3? Or a supposed new one off ebay? If it were me? I would do a new box and engine harness, but that's me not wanting to spend another small fortune on a 3rd box...

 

[3000gt]

I would buy a yellow label box from 86humv. He has NOS ones

 

[86humv]

I would buy a yellow label box from 86humv. He has NOS ones

Got no more NOS ones anymore.

 

[1 Patriot-of-many]

Well....he found the culprit. See pics below of inside the control box. This was aledgedly a new box from a previous repair. I have a few questions...

1). What is the likely cause of this getting fried out?
2). Is this repairable? Like trying 2 new transistors? Or is a new box needed?


Also, on the mechanic front, I think I have a guy I trust. He's a full time diesel mechanic and also maintains a Deuce in the fleet. He's the second guy I've gone to, and he's a good guy and trying to help me.

I've got an old box with one of those same Mosfets blown. I since bought a new esss box, but I plan on desoldering it eventually and replace the mosfet. My cousin thinks there's more to why it blew than just the mosfet but it's worth a shot. I bought a little pack of 10 of them. If you send me a PM or email, I'll throw a couple in a package for you. Otherwise just look for them on on the usual sites, they are pretty cheap. Should be RFP2907 http://www.steelsoldiers.com/showth...-new-box-and-sensor-for-the-glow-plugs-system

 

[WalterMitty]

I've got an old box with one of those same Mosfets blown. I since bought a new esss box, but I plan on desoldering it eventually and replace the mosfet. My cousin thinks there's more to why it blew than just the mosfet but it's worth a shot. I bought a little pack of 10 of them. If you send me a PM or email, I'll throw a couple in a package for you. Otherwise just look for them on on the usual sites, they are pretty cheap. Should be RFP2907 http://www.steelsoldiers.com/showth...-new-box-and-sensor-for-the-glow-plugs-system

I'm with your cousin. My mechanic wanted to just repair the currently fried PCB, and see if that worked. But my feeling is that there's probably something else going on that allowed it to fry out in the first place. So I'm going with a new PCB and matching TSU. I'm also replacing the engine wire harness, as maybe that's the real culprit. Having said that, I will PM since it would be good potentially have a repaired spare PCB...especially given that they cost so much.