Obd2b to Obd1 Auto

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Kevs02Accord

New Member
Hey guys I am trying to see if its possible to do an obd2b to obd1 auto conversion. This is for my 2002 accord. I will be using a 94 accord TCU and P75 ecu. I know someone who has done an obd2a to obd1 auto with success but the pins are different. So I need some help. I have attached an excel file with the obd2b, 94 tcu and p75 pins. I have attempted to show the connections from the obd2b to the ecu and tcu. There are several pins that I cant figure out were they go, can you guys take a look and see if you can match the missing pins. The list of missing pins from the obd2b pcm, 94 accord tcu and p75 ecu are listed at the bottom. Additional questions are;

1. With pins that have more than one connection is there 2 wires that come out for example obd2b pin A17 to TCU pin A22 and P75 pin A15?

2. Do I have to route any wires from one pinout on the ecu to the tcu and vise versa?

3. Will the missing pins from the p75 ecu and 94 tcu cause a malfunction?

4. Will the missing pins from the obd2b pcm cause a malfunction?

The obd2b pinouts were obtained from helms, the other pins were provided by the person who did the obd2a auto conversion. I feel fairly confident in the p75 pins, I verified them with several sites, however there are a few with some questions. I have not been able to confirm the tcu pins, so if anyone has those that I could check that would be a big help.

Any help you could give would be very appreciated.

Auto OBD convert info Full.zip
 
Any one had a chance to take a look? I was talking with a guy on another form, he seems to think there will be problems since there are several controls that the obd1 tcu can not account for, such as solenoid C, among others. How involved would it be to swap the tranny to an obd1? His main concern was the half shafts. What would some of the problems be?
 
I am in the middle of doing an OBD2 to 1 swap on a 97 civic auto. I got a jumper wire kit and chipped ecu from rywire. I had to re pin a couple things to get the stock 97 harness to work with a 2 wire iacv but that was no problem. My problem is that the transmission doesn't work now. Wont shift out of park without manually unlocking the shifter and then starts out in third gear. I thought this was a bolt in thing, but the stock 97 auto trans doesn't seem to work with the obd1 ecu. Anybody know what to do?
 
Auto OBD2>OBD1 conversion for Accords [COMPLETE] - Accordingly Done

Here is the write up which I have based most of my stuff off of. There are some very specific things you have to do to actually get it working. I am not sure how this will work with your civic application, I am guessing its similar. According to the write up you need a p75 ecu with an obd1 tcu, your car is obd2a pcm, all in one, I believe.
 
I am in the middle of doing an OBD2 to 1 swap on a 97 civic auto. I got a jumper wire kit and chipped ecu from rywire. I had to re pin a couple things to get the stock 97 harness to work with a 2 wire iacv but that was no problem. My problem is that the transmission doesn't work now. Wont shift out of park without manually unlocking the shifter and then starts out in third gear. I thought this was a bolt in thing, but the stock 97 auto trans doesn't seem to work with the obd1 ecu. Anybody know what to do?
Which ECU did you get for your conversion? Are you positive that it is from an automatic car as they are different inside, the pins are the same in the connecting plugs but a manual ECU won't work. I used a P06 .
 
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