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Wideband on D14 only reads 3.xx volts MAX

Posted: Sat Aug 22, 2009 3:19 pm
by KinZee
Got a bit of a problem... My AFX wideband reads 9-16 AFR from 0-5v but my D14 input on my ECU only reads up to 3.xx volts at MAX, and this equates to 14.5ish AFR. It makes it kinda hard to interpret datalogs sometimes. What do I need to do to get ECTune reading my widebands FULL 0-5v input? I have my wideband tab setup properly, and the readings cross over perfectly from the gauge to my datalogs. THANKS!

Posted: Sat Aug 22, 2009 5:52 pm
by 1337EJ1
3.80V max Its normal, ECU can't read more. You can mod you ECU for full 0-5V read, there is topic on pgmfi for that ;)

Posted: Sat Aug 22, 2009 9:08 pm
by KinZee
1337EJ1 wrote:3.80V max Its normal, ECU can't read more. You can mod you ECU for full 0-5V read, there is topic on pgmfi for that ;)
Well... that kinda sucks. Happen to have a link to the write-up on PGMFI? Well, now that I think about it, howcome the ECU can receive a 4.x volt TPS & MAP signal??? doesnt make much sense. I guess this is because narrowband O2 only uses 0-1v. Can I wire my WB up to a different input? which would be suitable for full 5v operation.

Posted: Sat Aug 22, 2009 10:20 pm
by Bugermass
YOu can use the ELD input.. Theres 2 resistors you have to remove. Look on PGMFI theres a thread on which ones to remove. But once you do this it'll work perfectly.

Posted: Mon Aug 24, 2009 11:42 pm
by calvin
you can look in setting of ectune too... it should be written there.

Posted: Tue Aug 25, 2009 2:17 am
by TopMountGSR
I have an afx and use EGR D12 with no issues.

Posted: Tue Aug 25, 2009 8:38 pm
by KinZee
TopMountGSR wrote:I have an afx and use EGR D12 with no issues.
OK, thanks... Did you have to remove any of the resistors in question? Also guys, I cannot find this write-up. Does anyone remember the thread title or have a link. I cant seem to get a good result with Google. ECU is an OBD1 USDM P75

Posted: Tue Aug 25, 2009 9:59 pm
by JaredKaragen
http://www.pgmfi.org check the wiki for ECU specific hardware questions ;)

Posted: Wed Aug 26, 2009 5:40 pm
by 98vtec
use eld (D10) and disable ELD in eCtune. no modification needed.

Posted: Wed Aug 26, 2009 11:59 pm
by chepetrueno
sorry to thread jack, but im using a lc1 and couldnt you just reprogram the wb to give 0.1-3.57v ??? would it be good that way

Posted: Thu Aug 27, 2009 1:47 am
by calvin
chepetrueno wrote:sorry to thread jack, but im using a lc1 and couldnt you just reprogram the wb to give 0.1-3.57v ??? would it be good that way
yes you can or use serial logging

Posted: Thu Aug 27, 2009 6:43 am
by TopMountGSR
98vtec wrote:use eld (D10) and disable ELD in eCtune. no modification needed.
We have had some issues trying this.. There is some sort of restriction on the ELD input. I can't recall exactly what it is at the moment but I am almost 100% sure you will have issues trying to run a 0-5v on ELD. Using EGR required no modifications.

Posted: Tue Nov 24, 2009 5:16 pm
by MantisX
Hi, just to confirm before I switch my wiring, using D12 will read 0-5 volts with no ECU modification? Thanks MantisX

Posted: Wed Nov 25, 2009 3:12 am
by Bindegal
I once investigated the various analog inputs with Calvin. If you follow the directions we put in the eCtune settings about replacing the resistors with 1Mohm units you will be fine. The basic problem is that the original resistors are 1K ohm. Ahaa so what does that mean? Well it means the output of whatever you´re connecting needs to pull anywhere from 2.5 to 5 milliamperes to drive that input. And widebands etc. are not designed to do that. Hence, replace the resistors with something much bigger. Rather than just yanking them out, this will ensure you have at least some protection against ESD and such and it won´t mess with the readings. Done this way, D10 works fantastic. /Allan

Posted: Tue Jan 05, 2010 5:45 pm
by MantisX
Im still stuck on this. Should I just do the 0-5v mod on D14 and screw the other options? No one seems to have a straight forward answer on the others(D10, D12) MantisX