98-02 Accord 4 cyl to OBD1 Auto Harness Installation Instructions

Please be careful with this harness. The ONLY way to properly function the OBD1 Automatic Accord / Prelude transmission is through the use of the proper transmission control module/unit (TCM). It is recommended that you use the TCM for your specific application. On the OBD2 Accord chassis, the automatic transmission functions are controlled through the ECU. On the OBD1 setup, the automatic functions are controlled separately from the OBD1 TCM.

There are 8 wires that need to be connected for proper usage. If there are certain sensors that your engine/ECU does not require, just tape off that numbered wire and leave it unhooked. You will need to have a STOCK wiring harness where it plugs into the ECU (If you car already has these sensors installed, you do not need to remove them to connect them to the pigtail. They are already wired into the harness for cars equipped with VTEC, etc.). So, after you have a stock harness, plug the jumper harness into the stock ECU harness plugs and let's begin:

  • Connect the BLACK wire to the VTEC solenoid.
  • Connect the BROWN wire to the pink/blue wire from the IAB's off of the intake manifold (this is the switching trigger for the IAB's/secondaries).
  • Connect the RED wire to the black/yellow wire from the IAB's off of the intake manifold (this supplies +12v power for the IAB's.
  • Connect the ORANGE wire to the VTEC Pressure switch (connect to the blue wire on the VTEC pressure switch connector).
  • Connect the PURPLE wire the black wire on the VTEC pressure switch connector (this is the VTEC pressure switch ground wire).
  • Connect the WHITE wire to the shift lock control. If you do not install this wire, you will have to put the key into the console shift lock release to unlock the shifter. To install this wire, splice in the WHITE wire from the conversion harness to the Green/White wire at the shifter position switch. You will need to remove the console cover to access this multi-wired connector. NOTE: On some models the shift lock release may still not function and you will need to insert the key into the console shift lock release to unlock the shifter.
  • Connect the BLUE wire to the Sport/Normal shift button on your shifter if your vehicle is so equipped.
  • Connect the GREEN wire to the one wire knock sensor located on the back of the block. It is the one-pin connector located above the oil filter.