The 94 prelude has an electronic load detector (ELD) which is part of the charging system. My 91 lude doesn't have one. The 91 uses relays in the under hood relay/fuse box to do the same thing as the ELD in the 94. The ELD sends an input (green/black wire) to pin D20 in the ECU. My question is, can you convert the 94 to the 91 without the ELD or do I have to buy one????