Hacking up Honda's ECU
It is currently Wed Mar 20, 2019 8:01 pm

All times are UTC - 5 hours [ DST ]

Post new topic Reply to topic  [ 1 post ] 
Author Message
PostPosted: Sun Dec 07, 2014 1:45 pm 

Joined: Tue Mar 09, 2010 2:02 am
Posts: 3

last year I converted my EDM Civic EG8 from DPFI to MPFI using P1K ECU chipped with P30 basemap + D15B7 fuel/ign. Had some issues with O2 heater error (CEL41) - the map had O2 heater enabled, I didn't have access to EPROM burner anymore, no heated O2 sensor (only 1wire), no heater harness in car and even no O2 heater related components mounted on ECU PCB, so I decided to fake O2 heater signal to MCU - corresponding 82C55 expander input fed with inverted (4069 CMOS added) O2 heater output (see ), works fine :)

Now I tried to convert ECU from nonVtec to VTEC - board was the most similar to 11F0 so I added IC14, Q101, C60, D11, shorted J10, verified presence of R201, double checked everything. Used chip with P30 basemap and D16Z6 fuel/ign, VTEC on. IC14 is SK5050 with mod described here, before mod I got CEL 21, now I have CEL 22.

CEL 22 even with A4 - D6 shorted. Tried to trace the signal way of VTEC pressure switch (my improvised schematics), tried to feed 82C55 pin 34 with GND, +5V, copy of VTEC solenoid signal, inverted copy of VTEC solenoid, .. no way, still CEL 22.

I don't have VTEC head yet, I just want to take advantage of two maps switchable the same way as VTEC; VTEC solenoid is replaced by resistor and LED indicator.

Any suggestions? Normally I would burn chip with VTP disabled, but my new EPROM burner is now on the way from China and I'll get it probably in half of January.
I suspected missing some components in VTP signal flow, but faking VTP signal on 82C55 expander failed so ..

Thanks in advance, dj-bobr /CZ/

Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1 post ] 

All times are UTC - 5 hours [ DST ]

Who is online

Users browsing this forum: No registered users and 13 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

Powered by phpBB® Forum Software © phpBB Group