M998 Humvee Running Light, Headlight, and Turn Signal Issue

[Lit_Armo]

Hi I have an M998 with a few issues and I wanted to see if anyone has advice. My front ride side running light (the bulb above the turn signal bulb) is not working, the R turn signal works. My right side headlight would work in high and low beam, but now it started working only in high beam. Also, the front turn signals are weak unless I press the turn signal lever inwards little, like im bending it forward, or when I compress the signal lever system like a sandwich between my hand.

I tried cleaning the corrosion in the R running light bulb housing, but still nothing. My left running light works but it gets so hot it melts the plastic amber cover, I think it's because only that side works and the right doesn't?

I took apart the turn signal lever and cleaned the circle metal ring contacts with rubbing alcohol, it made my turn signals work but its not 100% working like id like.

 

[Mogman]

Welcome to the forum!!

 

[Lit_Armo]

Welcome to the forum!!

Thank you I just bought my first Humvee!

 

[williamh]

I would start by checking for broken wires and bad grounds. Melting the cover are you sure the correct lamps are in the correct receptacle ? The top lamp should be for turn signal and middle is for parking lights. Bottom is blackout turn. I’m pretty sure.

 

[Milcommoguy]

Bad Pictures worth about 340 words.... Got to like pictures, CAMO

 

[Lit_Armo]

I would start by checking for broken wires and bad grounds. Melting the cover are you sure the correct lamps are in the correct receptacle ? The top lamp should be for turn signal and middle is for parking lights. Bottom is blackout turn. I’m pretty sure.

Thank you I'm going to get a better look at the wires and clean more corrosion.

 

[Lit_Armo]

Bad Pictures worth a 340 words.... Got to like pictures, CAMO
View attachment 901269

Appreciate your help, I need to use a #6 bulb for running lights, will try those.

 

[Warhammer1]

Hi I have an M998 with a few issues and I wanted to see if anyone has advice. My front ride side running light (the bulb above the turn signal bulb) is not working, the R turn signal works. My right side headlight would work in high and low beam, but now it started working only in high beam. Also, the front turn signals are weak unless I press the turn signal lever inwards little, like im bending it forward, or when I compress the signal lever system like a sandwich between my hand.

I tried cleaning the corrosion in the R running light bulb housing, but still nothing. My left running light works but it gets so hot it melts the plastic amber cover, I think it's because only that side works and the right doesn't?

I took apart the turn signal lever and cleaned the circle metal ring contacts with rubbing alcohol, it made my turn signals work but its not 100% working like id like.

Hello Lit_Armo, i ran into the exact same problem that you described on my '93 M998A1 - everything worked fine until one day it didn't (symptom you described). I followed great advice from my Steel Soldiers peers - verified continuity/condition of wires to all external lights, checked grounds, verified bulb conditions and also multi-metered the original turn signal pins (TM had a pinout diagram). No dice. I finally gave up and just replaced the expensive OEM turn signal with this cheaper one ($50 or $70 ??) and everything auto-magically worked. Hoping this gets you closer to a fix.

 

[Lit_Armo]

Hello Lit_Armo, i ran into the exact same problem that you described on my '93 M998A1 - everything worked fine until one day it didn't (symptom you described). I followed great advice from my Steel Soldiers peers - verified continuity/condition of wires to all external lights, checked grounds, verified bulb conditions and also multi-metered the original turn signal pins (TM had a pinout diagram). No dice. I finally gave up and just replaced the expensive OEM turn signal with this cheaper one ($50 or $70 ??) and everything auto-magically worked. Hoping this gets you closer to a fix.
View attachment 901436

Thank you if my corrosion repairs don’t fix the issue I’ll look into changing the lever or the whole signal housings/headlights

 

[Milcommoguy]

Hello Lit_Armo, i ran into the exact same problem that you described on my '93 M998A1 - everything worked fine until one day it didn't (symptom you described). I followed great advice from my Steel Soldiers peers - verified continuity/condition of wires to all external lights, checked grounds, verified bulb conditions and also multi-metered the original turn signal pins (TM had a pinout diagram). No dice. I finally gave up and just replaced the expensive OEM turn signal with this cheaper one ($50 or $70 ??) and everything auto-magically worked. Hoping this gets you closer to a fix.
View attachment 901436

NO serial number... NO bueno. Translated... Not Made in AMERICA. Guess if it works, Okie Dodkie.

Sorry for the message in the fortune cookie, CAMO

 

[Lit_Armo]

Quick update on my turn signals and headlight issue.

I fixed the problem with my turn signals and running lights not working. For the turn signals I took apart the lever and cleaned/electric greased the metal contact ring. And cleaned/ electric greased the bulb fitting. Works now!

For the running lights, the fix was cleaning/electric greasing the corroded and unplugged wires behind the marker unit, underneath the hood.

Anyone else with these electric issues I would clean off corrosion and the plug connections with a nylon brush and rubbing alcohol to remove corrosion, and put a dab of electric grease in the contact. For wet areas even wrapping it with electric tape over the plugs is a good idea.

Tried to fix my headlight but I need a new one, I think the low beam is fried.

 

[Milcommoguy]

IMO... Might be a bit overkill with the tape. Those simple rubber"Packard" style connectors have been thru a lot of wars with very good service life.

Depending on the environment, they can crack, become brittle & show signs of "jungle rot" That's a real mess up one IMO, LOL.

Those didn't look bad at all. What to watch out for on any connection is corrosion and sounds like you "nipped it in the bud"

More problems with the steel light bulb sockets in the rig with with rust and the ground wires to steel nuts and bolts in all area. Not sure... pop the lens off the turn-stop buckets & side markers and take a peek. Favorite hiding spot for gremlins LOL.

This type of troubleshooting with follow up & a little TLC will last another 40 years. Dielectric grease keeps them sealed, slipping and sliding.

Tape option.... optional, IMO. Could be a sticky ? Mr. moderator.

Everybody has one... or two, CAMO

 

[Lit_Armo]

IMO... Might be a bit overkill with the tape. Those simple rubber"Packard" style connectors have been thru a lot of wars with very good service life.

Depending on the environment, they can crack, become brittle & show signs of "jungle rot" That's a real mess up one IMO, LOL.

Those didn't look bad at all. What to watch out for on any connection is corrosion and sounds like you "nipped it in the bud"

More problems with the steel light bulb sockets in the rig with with rust and the ground wires to steel nuts and bolts in all area. Not sure... pop the lens off the turn-stop buckets & side markers and take a peek. Favorite hiding spot for gremlins LOL.

This type of troubleshooting with follow up & a little TLC will last another 40 years. Dielectric grease keeps them sealed, slipping and sliding.

Tape option.... optional, IMO. Could be a sticky ? Mr. moderator.

Everybody has one... or two, CAMO

Thank you I went with the tape wrap because some of the rubber plugs were cracking and ripped. I wanted to overkill to not have to do this again for a very long time haha.

 

[mgFray]

I've come to the point where I just have a container of the packard connectors. As I do things on the HMMWV. If those old connector is damaged in ANY WAY, I remove the old one and install a new one. The amount of cracked or broken boots.. or connectors missing the little ring on my rig was very surprising to me.. but I suppose 1988 to today is a long time for the truck. (Note, seems to be worse on connectors exposed to the elements or on things that required occasional servicing.. not a huge surprise!)

I usually buy my connects in 10 packs from Eriks'. Just remember that 12 AWG and 14AWG have slightly different boots, so best to have a set of both, along with some Y and connector pieces.

My "go to" package has 10 of each type of package, 4 male/male connects, and 4 female Ys.

(And if you are new to packard connectors.. male/female is backwards. They call male/female by the BOOT, not the center. So the connector with the pin is the FEMALE, while the connector with the socket is the MALE. Took me a while to get my head wrapped around that.)

 

[Milcommoguy]

Thank you I went with the tape wrap because some of the rubber plugs were cracking and ripped. I wanted to overkill to not have to do this again for a very long time haha.

Got ya. Those rubber parts an easy / cheap replaceable item. Slip right on. Good to have some on hand. Epay item or....

Got em right here, boys and girls. CAMO

 

[Mikei998]

I have a m998 and my turn signals just quit working . Now when I turn left/right signal the green light stays on (no blinking) and both left and right do not turn on . could this be the same problem? Any info would be greatly appreciated.

 

[mgFray]

I have a m998 and my turn signals just quit working . Now when I turn left/right signal the green light stays on (no blinking) and both left and right do not turn on . could this be the same problem? Any info would be greatly appreciated.

Check your grounds at the lights. I saw similar behavior when the grounds were bad on my vehicle.. (I had to clean them all.)

If that doesn't resolve it, there are some trouble shooting steps in the TM that might help you, it's possible it's the blinker box.

 

[Mikei998]

Thank you for the reply! Are the blinker boxes universal. I see they on line just not sure if they are all the same or if there’s one specifically for the m998 ?

 

[Mikei998]

I have the one that runs led . But my truck has normal bulbs . Not sure if it’s correct? Here are the 2 I have seen.

 

[mgFray]

I believe there is an LED/Incandescent and a Incandescent only box. I'm not 100% sure, but I THINK all of the modern ones support both.