790 has no electric output at all

[markcg2000]

This is the third time in the last week... Turn the key, get the dash to light briefly, the starter just starts to engage, then the whole tractor goes dead... No lights, no dashboard indicator. Got out the multimeter. All the fuses, fusible links check out. Battery is good. The lights are not dim - they're totally off. Last two times I got frustrated, put it all together and she fired right up. This time I pulled the three main fuses. Voltage at the fuse box's main buss would drop to zero when I plugged in the 10 amp "indicator" fuse. Checking the schematics, I can't see anything downstream the would short out the voltage, but not pull any currecnt and blow the fuse.
I sure hope someone out there can help /forums/images/graemlins/frown.gif

 

[ronjhall]

My <font color="green"> JD </font> mower had a similar problem. Found that one of the ground wires did not have a good connection. Use your schematic and remove and check all the grounds.

 

[RoyJackson]

Definitely sounds like a loose or corroded ground. I'd start right at the ignition switch.
You may also have a bad ignition switch.

 

[Dutch445]

Especially check the battery cables,, they are a common
cause of problems like you are having.
/forums/images/graemlins/cool.gif

 

[BB_TX]

I am siding with the bad ground crowd. Go to an auto parts store and get one of the battery cleaning brush tools. Has a small brush that fits inside the battery clamp to clean that and a cup brush that fits over the posts to clean those. Sometimes a thin white powdery stuff will form on the post and/or clamps that is hardly noticeable but will cut off the contact between post and clamp. It that doesn't do it, then check the other end of both battery cables.

 

[markcg2000]

looks like I'll be Gound hunting tonight /forums/images/graemlins/frown.gif Hardest dang thing to find is a connection that is weak/intermittent. I'll let you know how it goes.

 

[markcg2000]

Seems you were right! I took the ground cable off the battery and disconnected it from the tractor. I wire brushed both ends 'till they shined. I was amazed to see that the paint on the tractor was still there! I used a screwdriver to scrape the paint off and get a good connection. Put everything back together and the lights came on. We'll have to see if the problem comes back, but so far, so good. Man, I love this forum!!

 

[andrewj]

could be starter relay, or starter cylinoid, or have you mashed the wire harness and possibly shorted two wires? im having electrical grimlins too.

 

[markcg2000]

I thought those might be the problem,too, so I was pretty careful checking them all out. As I said, the ground cable on the neg. terminal really needed that cleaning... and we'll see if this actually did the job.