Reverting s300 ECU to ROM Socket

s300 and SManager software questions & answers
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7rrivera7
Posts: 130
Joined: Wed Nov 13, 2002 3:01 pm

Reverting s300 ECU to ROM Socket

Post by 7rrivera7 »

A customer bought a used Hondata P28 ECU with the OBD2a connector off of eBay for close to $300 dollars thinking it included the s300 - he was wrong. Since now he cannot afford an s300 board, he asked me to re-chip it - remove the s300 pins and install a socket.

Since I don't have an s300 board to test the ECU, I connected it to my Moates engine SIM with a custom OBD2a to OBD1 harness, removed J1 and it responded as an unchipped P28. I also installed it in my 1996 Integra (OBD2a) and she started up and reved fine so I proceeded.

After removing the s300 pins with professional equipment (I've been chipping and repairing Honda/Acura ECUs for 4 years) and installing the socket, I got a solid cell. I tested the entire chipping job, pin by pin on the socket, 373 latch, 541 buffer, RM3 resistor pack, J1 and R54 and I've got continuity and R54 has 1k of resistance (I used the PGMFI ECU chipping wirelist which has uncovered dis-continuity in the past with other ECUs). So right now, I've got a P28 with an OBD2a connector which runs fine with J1 cut.

Personally, I feel the following question is foolish seeing I can't see how it could be done running the stock code but here it goes anyway...

My question is if Hondata does something on their s300 P28 with OBD2a connector ECUs that prevents their use with a ROM socket? I'm preety sure Hondata will say NO but I lose nothing in asking.
7rrivera7
Posts: 130
Joined: Wed Nov 13, 2002 3:01 pm

Post by 7rrivera7 »

Never mind - I found a short between pins 5 and 6 on the socket.
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