HIYA! LMTV turn signalsand brake lights not working (when pressed)

[mikemike1079]

Hiya! I have a 1998 1079, and the turn signals, and brake lights dont activate when triggered, anyone have any tips? TY!

 

[NDT]

Is the light switch set to “service drive”?

 

[GeneralDisorder]

Yep. Have to turn the lights on. All military vehicle start out in "light discipline" mode. You don't even get blackout drive unless you select it. On the pushbutton switch you press any button to wake it up and then your desired mode and enter.

If you have service drive turned on and they still don't work.... Clean every ground in the truck (there's over 100), replace all the old style circuit breakers with blade fuses, replace all the relays with appropriate NEW 12v or 24v five pin relays and then report back results.

Turn signal stalks do fail. Have seen that multiple times. Also the pushbutton switches on the A1+ trucks can and do fail - usually because they have a poor ground either at their dedicated ground wire (lever switch does not have) or the PDP ground in the passenger grab handle or the cab ground behind the radiator (particularly naughty) or one of the MANY other grounds that likely need serviced badly.

 

[Ronmar]

Or for us 3 lever crowd, release the lock and rotate the left hand lever to service drive to power brakes and signals… beyond that here is a basic lighting diagram. Full details and component and wire numbers are in the official electrical diagrams in the back of every manual…

 

[mikemike1079]

AWESOME thank you yall! Ok the stalk does activate lights high and low beam, I got it to service, all lights work (stationary ones) but blinkers dont, one thing I noticed as well... there is no Switching clicking noises from the panel with relays...
im gonna start there first, and that you yall! I just put new head lights on and I will be converting it heavily to the (Drive the Globe) style military truck., will uplaod pics soon

 

[Ronmar]

The oem solid state flashers are a pretty high failure item, and this design has the flasher pulsing 100% of the time. Y0u can disconnect it(under passenger dash) and put a jumper across pin A-B which, if power is available on pin A, will send power thru the rest of the circuit for testing. I replaced mine with a commercial 12A unit made by grote…

The only thing that clicks in the signal circuit are K30 and 31, but these are for 24v trailer power and no-one I know has a 24v commercial semi-trailer. K06 and K10 should go click when you step on the brake pedal(must be air in the tanks to activate the pressure switches on the treadle valve…