Re: (ET) Problem with E20

[steves <ssawtelle erols com>]

Actually sounds more like an open than a short.

First don't jumper across the varistor connections. The varistor should 
act as an open circuit until a transient  comes along, then it starts to 
conduct.

I suspect a bad connection to a relay, or more likely, the card. The 
card connectors are not the best design. With the panel open, wiggle all 
the wires one at a time and I bet you'll see the problem show up at some 
point. With luck you can tighten up that terminal.  A more proactive 
stance would be to clean up all the connections with some scotchbrite 
and/or contact cleaner and give each terminal a bit of a tweak with 
pliers to make them fit tighter. You may find terminals that are cracked 
or broken - replace them. This is both for relay and card connections.

- SteveS

.

Kleinbrahm, Bob wrote:

> I am experiencing a problem with my E20 that I am hoping someone can 
> help me with.  My tractor seems to have only 3 speeds forward now.  I 
> have checked the #4 card and it looks good and I have cleaned the card 
> edge connector, etc.  The other day, the tractor stopped running 
> altogether, no drive motor at all.  I was able to flick the f/w switch 
> into reverse and it started to run again, as well as forward now.  
> Next day I decided to look into it a bit more and the tractor was dead 
> again.  Switching to reverse didn't work this time so I unscrewed the 
> control board panel with the relays on it and checked each relay for 
> proper alingment etc.  When I tried motor with the control board in 
> the down position, it started to work again.  Thought maybe I had a 
> short somewhere that was causing this, but I cannot find one as of 
> yet.  When I press foot pedal the motor starts speed, and then slowly 
> move the panel up to the correct mounting position, the power cuts out 
> again, and will not function in the mounting vertical position.  I 
> noticed that with the foot pedal depressed slightly and the control 
> board half way back up, the fw relay starts to chatter right before 
> loosing all power.  Shouldn't the fw relay function for the first 3 
> speeds?  In troubleshooting this I also noticed that the #3 card had 
> the varistor burned and indeed the traces were gone from it.  I tried 
> jumpering the card accross the edge connectors that the traces lead 
> to, but it immediately began to smoke the jumper wire when I applied 
> power.  I have a new card from Harrold but do not want to install it 
> until I can figure out why it is drawing so much current.  I know this 
> really sounds like a short somewhere and will start to trace each wire 
> as time permits.
>  
>  
> Bob K.