obd0 main relay and wires to obd1

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boostfreak 417

New Member
I have ran into a problem i have a 90 civic just swapped to d16z6 ive got a bad main relay. I looked at the main out of the 95 coupe donor car, it looks like it a lil bit dif, is there any way cut the wires on the 95 coupe and wire them to the 90 and make it work, has anyone done this or know how too?
yes, you can use the connector and relay from the 95 - just match wire colors at each pin - both the 95 and the OBD0 have 3 pins in the top row with an empty slot - the empty slot is in different location on each - on the 95, you will have 2 wires that are different color from the OBD0 wires - the 95 has a green/yellow wire where the OBD0 has a green/black wire at the same pin - connect the green/yellow wire on the 95 connector to the green/black wire on the OBD0 harness - the 95 has a yellow/green wire where the OBD0 has a yellow/black wire at the same pin (end pin on bottom row of 4) - connect the yellow/green wire on the 95 connector to the yellow/black wire on the OBD0 harness - please note that the OBD0 harness has 2 yellow/black wires - don't get them mixed up
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the car cranks over but doesnt start brand new bat, new alt, main relay, all grounds are good and have clean connection. no fuel no spark, oil, battery, and cel stay on when i remove the key
ICM=ECU You know that rectangular box on the passanger footwell, thats your ECU. You buy a conversion harness or make your own? And does the relay click when you turn the key on? Any blown fuses?
no ecu is perfectly fine. yes wiring is all ran right, all fuses are good, i usually leave the battery terminal off unless im messing with it but when i connect it and turn the key fuel pump primes then wont until i repeat that step?
yes bought a harness from monotech it was sent with obd0 dizzy plug i had to cut and rewire, all matched except for two on the harness and two on the clip. on the clip there is a blue/grn and blue/ylw, on the harness there is a ylw and then a blk/ylw do you know which gets wired where or if that could be the prob?
i dont have the 02 sensor wired up yet they sent the harness with single wire 02 sensor when i specifically told em it was obd0 to obd1. but the jumper has wires for the 02 so i think i should be good. would this cause the symptoms by not having the 02 wired up
I dont think so but it could. My car wouldnt even run took me two days to figure it out and it was my VTEC ground wasnt hooked up.