Lmtv no power on push to start

[Socommfg]

The wtec has no lights and the push button will not engage starter. I can jump the motor and it will run perfect. What am I missing?

 

[MGKMartin]

Sounds like a relay or relay panel problem. Which version A0 or A1?

 

[NDT]

Until your WTEC lights up you will not be able to start normally. Start your diagnosis by making sure the relays and breakers in the PDP are the correct part numbers in the correct spot.

 

[Suprman]

When you jump the motor are you jumping the fuel solenoid too or just the starter with the dash power switch on?

 

[Socommfg]

When you jump the motor are you jumping the fuel solenoid too or just the starter with the dash power switch on?

I took the cover off of the starter relay and pushed it in.

where is the AO or A1 designation?

 

[Socommfg]

I took the cover off of the starter relay and pushed it in.

where is the AO or A1 designation?

I took the dash out and some of the lower pins are corroded. What is a good way to clean them?

Then I can start with the wtec troubleshooting.

 

[NDT]

I took the dash out and some of the lower pins are corroded. What is a good way to clean them?

Then I can start with the wtec troubleshooting.

By "the dash" I am assuming the cover of the PDP and by pins I assume spade terminals on the plug in relays. I would replace any that are significantly corroded, otherwise use a wire brush.

 

[PowerstrokeNC]

subscribed

 

[Suprman]

24 volt power relay should actuate with the dash main power switch. This provides 24 volts to the trans control and fuel solenoid. Thru breakers of course. Corrosion on board contacts can cause issues. I have the replacement contacts and the plastic pieces that hold them into the board.

 

[Wags724]

Renewing thread. M1078A1P2. No power to start button. Hold button,flip main power and it starts. This works on both cab and remote start. Start button loses power 1.5 seconds after turning on main ign switch. Relays are all good. No corrosion found. Any help? Tia!

 

[Suprman]

Is all the power dropping out after the 1.5sec? I wonder if the batt disconnect relay is shutting off.

 

[NDT]

Renewing thread. M1078A1P2. No power to start button. Hold button,flip main power and it starts. This works on both cab and remote start. Start button loses power 1.5 seconds after turning on main ign switch. Relays are all good. No corrosion found. Any help? Tia!

I would start at the WTEC contol, any codes? Maybe what you are doing is fooling the contol by getting the engine started before the contol boots up and inhibits cranking because of something causing DNS.

 

[Floridianson]

Do not know if my problem is the same. My push button just started to acting up. Power off I sprayed the heck into the button electrical contact cleaner and pushed it 10 times. So far so good.

 

[Wags724]

Is all the power dropping out after the 1.5sec? I wonder if the batt disconnect relay is shutting off.

Actually, just found the issue as we speak. Trans Controller. Was for some reason acting like natural safety switch. Tried a good controller, works as it should.

 

[NDT]

Actually, just found the issue as we speak. Trans Controller. Was for some reason acting like natural safety switch. Tried a good controller, works as it should.

The trans controller HAS a neutral safety switch in it, in the VIM box.

 

[frank8003]

Electronics rule the world now
I hate electonics

 

[Ronmar]

The start circuit is in 4 parts.
1. The trans controller/neutral start contacts provide 24V to the start relay K1.
2. The pushbutton provides a path to ground thru the starter lockout relay K24(starter lockout keeps you from cranking a running engine) To energize the start relay K1 When the button is pushed.
3. K1 provides 24V down to the aux start relay on the drivers frame rail and the starter thermal sw provides the path to ground so K1 can energize the aux relay.
4. The aux relay provides 24V to energize the starter solenoid and crank the engine...