M998 flasher problem

[Chirider]

On my front left blinker, The Large bulb does not flash but the Small bulb flashes. Small bulb also flashes in the in the other socket where the large bulb should be. I have used a working large bulb too so it is not a bad bulb. What could the problem be? All other blinkers work.

 

[Mogman]

You probably have a grounding issue to that lamp housing.
the current is going through the large bulb and back feeding through the small bulb, of course only the small bulb will light because it takes less current than the large bulb.

 

[Mogman]

The wrong bulb flashing is a good indication of a grounding issue.

 

[springer1981]

Check the ground in the access panel inside the hood.

 

[Chirider]

Check the ground in the access panel inside the hood.

I now have opened the hood and honestly don’t know what I’m looking for. I did a search in the forum for access panel and no joy. So I am humbly asking for help again. Thank you and everyone.

 

[Mogman]

The panel is behind the lights

 

[Chirider]

I now have opened the hood and honestly don’t know what I’m looking for. I did a search in the forum for access panel and no joy. So I am humbly asking for help again. Thank you and everyone.

Perhaps the access panel is in here? This is directly behind the light housing that I am having a problem with.

 

[Mogman]

That is the panel that you need to remove to get to the wiring

 

[Mogman]

The ground wire is tag 92 and should be connected to one of the mounting studs for the composite lamp, there is a bar going between the two studs and that is your ground, it has to ground both studs, I suspect by the looks of the panel there will be allot of corrosion in there.

 

[springer1981]

Perhaps the access panel is in here? This is directly behind the light housing that I am having a problem with.

That cover as rusted as it is surely has let water in the wiring. Obviously you should replace the cover and probably the one on the other side as well. They cost about $20 each.

 

[TOBASH]

Silly question BUT can we be sure it’s not the switch?

 

[Mogman]

Silly question BUT can we be sure it’s not the switch?

Pretty much, it is sending the signal to the light, 98% positive it is a grounding issue due to the symptoms.
I suspect he will find the studs on the back of the light in the same condition as the cover panel.

 

[Mogman]

If you look at the picture above it is easy to see what is happening, the turn signal feed is going out on tag 461, but because there is no ground at the stud the current goes through the parking lamp seeking ground through the other parking lamps, only the parking lamp flashes, it is a smaller bulb than the turn signal lamp so not enough current flows through the turn signal lamp to make the filament hot.

 

[springer1981]

Don't overlook the ground strap that ties the 2 mounting/ground lugs together. I've seen one rusted right in half causing a similar problem.

 

[Milcommoguy]

Perhaps the access panel is in here? This is directly behind the light housing that I am having a problem with.

Ahhh, No problem. Just a little rust, CAMO

 

[TOBASH]

CamO makes a flasher device for this area, so he knows it quite well. If he says it is rust… it is probably rust.

 

[Chirider]

The panel is behind the lights

That cover as rusted as it is surely has let water in the wiring. Obviously you should replace the cover and probably the one on the other side as well. They cost about $20 each.

Can you recommend where to source the access panel? Indeed , the other panel is also rusted badly. I’m doing a search and using words, “M998 front light access panel” and not coming up with anything on google or eBay. Thx for ur help.

 

[Chirider]

Silly question BUT can we be sure it’s not the switch?

Another gremlin, coincidentally (I’m sure) after opening the access panel, my turn signals no longer work. The running lights work and brake lights work though. The light on the turn signal stalk lights up solid but doesn’t flash . In the past my turn signals would work intermittently so I’m not surprised. Could I need a new 3 lever switch?

 

[Milcommoguy]

If those covers could talk (LOL) they would have a heck of a story. Poking around and getting different problems... IS a problem.

These are all good question...and difficult to respond to. My best advice is to study the wiring diagram above. It is the "map" to this fix this problem. Wire tags are like highway numbers... so one shouldn't get toooo lost. Match the parts wires to the ....MAP, paying close attention to everything and clean , inspect all connections. reassemble with a little dielectric grease.

Having a short circuit could ?? have toasted the flasher unit. Don't forget to check out the hood to body connector. Could be a problem there with the clue of rusty covers.

Covers, one could make ? likely cheap from suppliers. Google search.

Failed grounds with multi bulb lighting circuits can send one for a loop. Follow the wires and don't get crossed up. Good luck.

Loopy and light headed, CAMO

 

[springer1981]

Can you recommend where to source the access panel? Indeed , the other panel is also rusted badly. I’m doing a search and using words, “M998 front light access panel” and not coming up with anything on google or eBay. Thx for ur help.

M998 L.H. ACCESS COVER 12338906, 5340-01-209-7834 NOS

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M998 HUMMER RH HOOD COVER ACCESS 5579675, 12338884, 5340-01-211-7436 MILITARY NOS

M998 HUMMER RH HOOD COVER ACCESS 5579675, 12338884, 5340-01-211-7436 NOS

equipmentpartssalespa.net