M998 REAR TAIL LIGHT LEDS

[Iambiig]

2 things here.

Should normal LEDs for the 623 and 1683 bulbs work in the rear tail lights without any issues?

My 1994 M998 has aluminum rear housings. There are places for 4 bulbs. Only the top 2 bulbs are installed in mine (623/1683). What are the 2 bottom bulb sockets for? What number bulbs go in them? The manual that I have only shows the plastic housings, which have LED chips in the bottom 2

 

[mgFray]

Bottom two are your blackout tail lights.

The aluminum and plastic housing are roughly the same, but the aluminum ones stick out slightly (or at least the ones I've seen do!

My 1988 has plastic rear tail lights, but the fronts are aluminum. I also have a spare set of aluminum I bought for the rear until I found they physically didn't fit in the openings on mine. Oops. Anyway, the sockets are all the same between the plastic and aluminum housings.

 

[williamh]

2 things here.

Should normal LEDs for the 623 and 1683 bulbs work in the rear tail lights without any issues?

My 1994 M998 has aluminum rear housings. There are places for 4 bulbs. Only the top 2 bulbs are installed in mine (623/1683). What are the 2 bottom bulb sockets for? What number bulbs go in them? The manual that I have only shows the plastic housings, which have LED chips in the bottom 2

The lower bays are for blackout stop and blackout driving. The numbers I don’t have unless I pull an assembly apart

 

[williamh]

The lower bays are for blackout stop and blackout driving. The numbers I don’t have unless I pull an assembly apart

Dang ur fast

 

[mgFray]

I found the following showing which bulbs go where:

BIG MIKE'S MOTOR POOL — M998 HMMWV PARTS

THIS SECTION IS CURRENTLY UNDER CONSTRUCTION, IF YOU NEED ANYTHING, FEEL FREE TO ASK MIKE!! BIGMIKESMOTORPOOL@YAHOO.COM

www.bigmikesmotorpool.com

 

[Iambiig]

1251's Excellent! Are there going to be any issues with installing LED's in any of these sockets?

 

[mgFray]

I'm not aware of any issues w/ 24V LEDs in any position.

 

[Iambiig]

Just tried the ones that I have. When the LED's are used in the 1683 position (2nd one from top) the turn signals do not blink. But with normal 1683 bulbs in, it is fine. They do work fine in the front though

 

[mgFray]

Just tried the ones that I have. When the LED's are used in the 1683 position (2nd one from top) the turn signals do not blink. But with normal 1683 bulbs in, it is fine. They do work fine in the front though

Interesting. With what I'd been reading I know that the newer blinker boxes work better with LEDs, maybe there isn't enough current draw for an older style box (assuming that is what yours has.)

 

[Mullaney]

Just tried the ones that I have. When the LED's are used in the 1683 position (2nd one from top) the turn signals do not blink. But with normal 1683 bulbs in, it is fine. They do work fine in the front though

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LED's generally require an "electronic flasher" to make the bulbs blink. They don't draw enough current to heat up the piece of metal (in the old mechanical flasher) enough to make it flex and cause the flash to happen. Cost for the electronic flasher is about 3x the old style - but it will generally last longer than you

 

[Iambiig]

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LED's generally require an "electronic flasher" to make the bulbs blink. They don't draw enough current to heat up the piece of metal (in the old mechanical flasher) enough to make it flex and cause the flash to happen. Cost for the electronic flasher is about 3x the old style - but it will generally last longer than you

ahh, yes. The flasher is probably still analog. Is there a part number for the digital one? And is it located under the dash?

 

[Action]

I have seen folks stick a regular bulb in-line and stow it in the compartments in the front of the hood.

 

[Mullaney]

ahh, yes. The flasher is probably still analog. Is there a part number for the digital one? And is it located under the dash?

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So, I may have lied. The official part from the military surplus dealers. Price is more like $50, possibly more. I wanted to give you the right answer. There MAY be other choices too - that I don't know about - but the Digital Flasher is definitely what you need to use LED signal bulbs in your truck.

The flasher is a ribbed black box mounted up in behind the ignition switch area. It's marked 'flasher directional signal' so there's no mystery about if you've found the right one. Before you swap out the box make sure you check the cannon plug for corrosion as well as all of the grounds you can find. (There is also a time delay module about the same size, ribbed, and also close behind the ignition switch)

A little more information:

LED turn signal issue

hi guys, new owner here. im having an LED turn signal issue. with the rotary selector in stop, my passenger turn signal is on, not flashing, just on. if i take the signal wire and switch it with the park wire on the light, the park light stays on. so im getting power to wire 460 when there...

www.steelsoldiers.com

 

[williamh]

You could just add an load resistor to the front light , had to do it to my work truck to make the led tail lights flash properly