2003 M1078 A1/ Tell me about the push button Light Switch Please

[Lugnuts]

Alright, color me stupid, I can turn on Stop Light and Turn Signals, and all lights off. That is the extent of it. I have two low mileage units that do the same thing so I figure it is me having the trouble. How to diagnose or how to work, that is the question.
Thank you guys.
Lugnuts

 

[Keith Knight]

press Ser Drive then enter for head lights. Most of the time I have to press enter very hard and hold it and sometimes multiple times. Some times repeat the process. The enter button isn’t the most responsive. I did open it up and clean some green oxidation off but it didn’t seem to help.

 

[Ronmar]

Yep, service drive and enter should enable the stop, turn-signals and headlights...

 

[Lugnuts]

Yep, service drive and enter should enable the stop, turn-signals and headlights...

If that doesn't work does it mean it broken or is it on a module?

 

[Lugnuts]

View attachment 939918
press Ser Drive then enter for head lights. Most of the time I have to press enter very hard and hold it and sometimes multiple times. Some times repeat the process. The enter button isn’t the most responsive. I did open it up and clean some green oxidation off but it didn’t seem to help.

You can open them up? Good to know. Anything special going to jump out or all self explanitory?

 

[Ronmar]

If that doesn't work does it mean it broken or is it on a module?

Check and make sure the switch assembly is properly grounded. They can act wonky when they are not grounded. You can also pull the switch and jumper the appropriate pins in the harness connector to enable brake, turn and headlights to test those circuits...

 

[Lugnuts]

I will check that out! Thank you

 

[TOBASH]

Are they backwards compatible with mechanical switches? On the HMMWV forum we hear these same electronic switches like to catch fire.

 

[GeneralDisorder]

Are they backwards compatible with mechanical switches? On the HMMWV forum we hear these same electronic switches like to catch fire.

Yes. But the push-button switches aren't supposed to be used on the HMMWV. They are for the FMTV, which has a 12v lighting system. The HMMWV lighting system is 24v - which likely has something to do with HMMWV's having them catch on fire AND it could be that they aren't being grounded properly as that has caused problems with these switches. They MUST be grounded, but the mechanical switch housing doesn't need a dedicated ground like the push-button switch.

 

[juanprado]

Narton makes a new model of the pushbutton that has a deeper face and fits the hmmwv dash better.

I have that on my hmmwv with no issues. Also have the other style on my m923. Both require a supplemental ground wire.