I just converted my p75 to vtec using the kit from xenocron, with a p72 basemap burned to the chip. Went for a drive around the block, no vtec and code 21, "open circuit to the vtec solenoid". So I unplugged the ecu and sent 12v directly to pin A4 or whatever it is in the harness, and the vtec solenoid clicks. Hence the wtf in the title.. I am all out of ideas on this one. I don't know what I could have fuc.ked up in the ecu, I was really careful. What could cause this? If it is the ecu, what should I look at? I figured I might have put that diode in backwards that goes to the vtec pin, but it's in the same orientation as all the other diodes..is there a certain other specific component that is likely to be the problem?
I emailed chris harris (xenocron) but he hasn't gotten back to me yet.
Any help or fresh ideas would be greatly appreciated on this one..

 

hey for ***** and grins,

connect like a multimeter to the vtec pin and the other to like A25/26 for ground and see if you get a 12volt output... when vtec is suppose to be active.

there's a couple things that can be happening, but try that first.

although putting in the diode backwards would cause it not to function might wanna double check the circuit there but as what I have found with working on honda's it's always something stupid man, it happens to everyone.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by likwidchz &raquo;</TD></TR><TR><TD CLASS="quote">hey for ***** and grins,

connect like a multimeter to the vtec pin and the other to like A25/26 for ground and see if you get a 12volt output... when vtec is suppose to be active.
</TD></TR></TABLE>

That's the same thing as sending power to that wire right at the harness connector like I did. There is no way there is power there, or vtec would work. No way around that. Right now I'm giving myself a headache looking over the ecu and trying to figure out how it works, or at least how a few simple sections of the board work.

 

..think I figured it out. I'll see in about 10 minutes..


Modified by rorik at 7:17 AM 6/14/2008

 

ehh, well hope you figure it out,

although its not the same thing as "sending power" its checking to see if it exists when it should exist..

start at the root of the problem and work outwards

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by likwidchz &raquo;</TD></TR><TR><TD CLASS="quote">ehh, well hope you figure it out,

although its not the same thing as "sending power" its checking to see if it exists when it should exist..

start at the root of the problem and work outwards </TD></TR></TABLE>

Well, if voltage "existed" at the pin, then vtec would have triggered, provided the load of the solenoid, about .6 amps, didn't "pull down" the output from the ecu. But if it did, then I wouldn't have gotten the code 21, "open circuit", lol.
Anyway, I did figure it out, xenocron's pic highlights j10, but his written instructions don't say/describe wtf to do with it, so I didn't know. I don't know if that's more his fault or mine. I usually drink beer when I tig or solder so my hands don't shake, but it's not like I get crunk..his instructions still suck. I had to find the info on pgmfi. Put the jumper in, no more code..

 

hahah I like how you overly explain it... that's hilarious...

well good deal..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rorik &raquo;</TD></TR><TR><TD CLASS="quote">
Anyway, I did figure it out, xenocron's pic highlights j10, but his written instructions don't say/describe wtf to do with it, so I didn't know. Put the jumper in, no more code.. </TD></TR></TABLE>

Good catch, I'll have to edit that...thanks and sorry