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Re: (ET) Or is it normal to see voltage without FU3 installed



That is an important clue that should not be taken lightly.It indicates
that somebody has "gone to chassis' and in fact the armature is the
prime suspect.You may also be surprised to find that the Fuel Level
Gauge has the same issue. If a high current path is essentially
established, life WILL get interesting. :( Start searching !

Not exactly. Pad 12 is the common neutral for the whole board, and although they did put in blocking diodes on the solenoid lines, there is a path from pad 7 to 12 through the 10k and 390 ohm resistor for Q104. Actually the same type of path is used for Q105, so the resistance is 1/R-1/r1+1/r2. Interesting, I wonder if they are how the card is supposed to sense armature movement and keep from throwing into reverse. A capacitor in an RC circuit on line 7 then might keep that line high after the armature is off long enough to let the field decay. Hm......

Anyway, pad 7 goes on wire 8 straight to the drive motor armature, then ground through the armature. So technically it's possible for the meter to read a value. However if you try to run a contactor or do anything the voltage drop across that resistor will drop the meter to zero.

So it's not quite a problem. Oddly enough I wonder if Q105 is supposed to 
be


RJ


Kim Petty wrote:
Chris, I just went out and tried it. When I take out the control fuse
and try to move the fuel gauge pegs on E and I hear relay chatter.
This happens on both the E12S and E15. Interesting side note. On the
E12S when I put the fuse back in it still did the same until I moved
the armature . Then it worked as usual. Kimball

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