Convert a Honda ECU from Automatic to Manual


Editors note: Originally published by Adam P. on his sub-site, Change Honda ECU from Automatic to Manual. Preserved here in the forums going forward.

This guide will help you identify and change or convert your automatic ecu to a manual version.

First, let's find out if we have an automatic, or a 5 speed ECU. If you don't want to plug it in and throw code 19 (automatic trans lockup solenoid) to find out it is an automatic ECU, then look at the code on the side. If the second to last number is a 5, then you have an automatic ECU (for OBD-1 USDM ECUs). If the 2nd to last # is anything but a five you have an ECU for a 5 speed. If you have a jdm obd-1 ecu, look at the last 3 digits: 900 or 901 will be an automatic. If you were unfortunate enough to get an automatic ECU, then read on and learn how to cure all your problems.
The following information was all obtained from Hondata: Honda/Acura Engine Management Solutions and the picture was graciously borrowed from them as well.

For Jdm Pr3/Pw0 ECUs:
Move the jumper from R68 to R67 (both locations are to the left of the ROM)

For USDM OBD1 ECUs (p28):
Underneath the ROM there is a row of resistors labelled with RP__ . Remove RP17 and install a jumper across RP18.

RP18 (in the same location as usdm) needs to be lowered in value from 2.4k to 1.4k ohms.