...continued.

If the LED panel is identified as bad by the preceding procedure, the
problem is usually the (lefthand) IC on the board, an LM324 quad
op-amp.  Radio Shack p/n 276-1711, $1.29 (US).  If you can do electronic
soldering and desoldering, it's worthwhile to just replace the chip and see
if that fixes it.  Or you can send it to me and I'll find the problem and
fix it for a lot more money ($30+ship, I think? I haven't done one in a while).

If the panel is not proved bad, first make sure that the meter you used has
at least 10 megohms input impedance.  You will *not* get good values with a
typical automotive-type voltmeter.   If that's not it we can discuss it
further.  Based on the symptom I think it's the panel.

david
David Beierl - Providence, RI
  http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"