Police M998 Wait light issue

[Cbrennan]

Hey guys!
Police officer here in Georgia and we got a M998z After receiving a shipment of a m998, the wait light worked perfect. One day we went to start it and it didnt without fluid and I realized no wait light. So I took the plugs out and inspected and went to AutoZone to buy new ones but they didn't have any, so I put old ones back in and the wait light starting working out of no where, and it worked great for a long time. So today comes and I get a shipment of correct plugs. Go to pull her in garage to work on it to replace plugs (mind you light worked prior to shutting her off) and I put new ones in, put antiseize on the threads and she's in. But I go to check light and it came on for a quick second then I tried to cycle it again and none. I waited and none again. It starts but clearly it takes long since no plugs are warming. I checked the boot ends and they seemed tight so I'm lost since it worked I don't think its box? Please,any help as this is an active vehicle for SWAT and inclement weather. Thanks so much

 

[BLK HMMWV]

How old are the batteries ?
Are they fully charged.
Most likely it's your glow plug controller.
Might be a loose ground as well.
Crazy things happen to the control box when your batteries are low.
under voltage can fry it , over voltage can fry it.
Disconnecting it with the batteries still connected can fry it.
HMMWV's are notorious for having parasitic drains in the electrical system.
As well as bad grounds . A ground harness is highly recommended on them if you don't already have that upgrade on the one your working on.
The 6tl batteries don't do to well sitting for long periods of time they need to be used. They need to have the fluids in the cells checked and it is recommended to swap positions every once in a while as the #1 battery seems to get the most work out.

Fluid ?? what fluid ? you used starting fluid ??


I know the trucks are free for agencies but they are maintenance intensive.
Hope you have a full time mechanic at your station.

 

[Cbrennan]

Hey man thanks. Starting fluid I know it's bad and brand new batteries . Light worked literally fine until I unplugged plugs. You think that controller can be bad if it worked before?

 

[BLK HMMWV]

Do you hear anything when you turn on the switch. Do you hear a clunk sound from under the dash?
What color is the label on the control box .

Key switch or the double lever original type

 

[BLK HMMWV]

Steel Soldiers has a nice technical manual section.
At the top of this page you will see a tab for technical manuals click on that and then select the present conflict vehicles the 4th one down might offer you some insight. ( EESS info)
Good luck.
It is strongly recommended to obtain a set of maintenance manuals for your new maintenance nightmare.
Good luck
BH

 

[Cbrennan]

I sure do hear that clunk. I'm not at unit now, I will be tom am and will let you know. It's got a lever switch that has run and start

 

[BLK HMMWV]

First thing I'd do is make sure both of your batteries are fully charged.
Is it cold where you are right now.
Has any maintenance been done to truck or did you just get it and drive it.
Most of them being released have been sitting for a long time , as well as not always in the best shape mechanically.
They may just throw some spare batteries they had laying around in them to start them and load them on a truck so they are always suspect.
Check for water in your fuel.
up under the front drivers side wheel well is a petcock for bleeding the water out of your filter/ separator
You may want to check to make sure your getting fuel there when someone is trying to crank it.

 

[jeffy777]

To me it is in order of probabilities:
1. The Batteries
2. The Ground
3. The Control Box.

Don't try and use a 12V charger on it. You can only do that if you take the batteries out and charge each battery individually. If you have 24V Charger make sure you put on the right battery. Only put your clamps on the post where the batteries are not connected to each other. See picture:


I bought a 24v charge/starter so I could debug this issue quicker as it looks to the system as a fresh battery and the wait light behaves normal.

There is also a section on install a new ground here on steelsoldiers: http://www.steelsoldiers.com/showthread.php?153367-HMMWV-Grounding-Kit-Install

The control box I think is easy I have yet to do it or read an example of someone doing it.

 

[zout]

You probably already know this but even if it were brand spanking new....mechanical & electrical are man made....they can take a crap whenever they want to and are least expected.

As mentioned above...download the TM..Technical Manual and at least you will have a fighting chance...without calling in the SWAT TEAM.

 

[Retiredwarhorses]

Can you verify the glow plugs you installed are 24v and not 12v?
Also, keep using that starting fluid and you won't need to worry about a glow plug light...you won't have an engine to start.

 

[Cbrennan]

Thanks so much y'all are a solid crew: I'm about to get off night shift and head there. Batteries are brand spanking new from NAPA (I got them). They are the commercial type and not the military ones tho. I'm going to get my jumpers and ground the neg EESS to the negative at the battery and see if I can get somewhere. Again thanks so much guys this means so much for all the help.

 

[Cbrennan]

Also, the part that gets me is it worked flawlessly before I changed plugs . I even put old ones back in and pulled boot up to make sure connection was good, but then again I was exhausted and it may as well be a bad ground causing not the right voltage.

 

[Socommfg]

Check the glo plug control module on the engine. It screws into the front right side of the intake. It turns the plugs on and off by water temp.

The loud clunk under the dash is the EUC. It stops feed back from the alternator and killing the batteries. They are easy to rebuild. It take a power trans. and a continuous duty 24vdc relay.

 

[Cbrennan]

Do you know if that module operates when there is no circuit it turns plugs on or when it gets 24v? Or is it a simple switch . And I hear the clunk do you think I still need rebuild

 

[BLK HMMWV]

Where did you get the plugs from?
Are they 12 volt or 24 volt?
Did you read the link to the technical manual I referred you to .
Odd it quit right after you changed plugs but if you didn't use the right plugs that might be your problem.
Spend some time looking through the TM's

 

[Cbrennan]

So I turned on my Humvee to run and bam wtf it worked. But I have the old ones in. I put the new ones in halfway and it still worked but when I put the boot over it quit which makes me think I got a bad connection. I went to go get the connectors and am going to redo it all. My question is do I need the boot over it? The connectirsbi got are snug but don't got a boot

 

[Cbrennan]

Redid all connections and no glow light but the battery terminals are all bad and loose so I think that's the issue. I'll let you know

 

[Socommfg]

Solid battery connections are required..

 

[Cbrennan]

So I just came back and it's working out of no where! I went for a ride and let t sit for an hour and she still works. I'll keep all posted THANKS SO MUCH EVERYONE

 

[bikeman]

dirty electrical can give these (and most other) trucks some nasty fits. Keep on the Maintenance. Be sure you guys are performing PMCS properly. Especially with the cold weather coming in. (esp presuming you're at Woodstock, WI)