HI

i was observing that with the WB grounded to the ECU the
TECHEDGE out put was different than what ROM EDITOR saw
i tried the Diode thing hondata suggests to no avail

SO

then i grounded it to the battery and POOF
the voltages were pretty much the same
so i went out and tuned it a bit
and it logged the CORRECT A/f ratio

YAY




[Modified by Usdm ED9, 1:41 AM 11/16/2002]

 

iv got to do this tonite !!

so your ground is taken directly from the battery... what about your positive ? where do you take that from ? just any iginition source ? like normal

Regards James

 

12V @ ecu wires
ground to batt/Front amplifier Ground (chassis)

 

INTERESTING. Hondata has been saying to make sure you ground wideband ground to ECU signal ground. I haven't been able to find anyone's who voltage matched until today. Have't found anyone who the Diode trick has worked for either. There is a thread in Tech under obd0/1 where Jhill does the same thing to get his to work. Looks like we need to ground to chasis ground.

By the way, this doesn't seem to be a Hondata problem...someone else who's using an EMS's voltage is off the same as well. I thikn we are just getting bad advice on how to ground the wideband signal ground.


[Modified by true, 4:18 AM 11/16/2002]

 

Welp i talked to Hondata today
they told me to try different grounds
i have it set up like this
pardon my ghey drawings

 

 

Very nice... This is very weird though... I tried connecting the +12v directly to the battery and the ground directly to the battery and it didn't work..? If you connect the +12v to the ecu rather than the battery should it really make a difference? Also, are you using the diode at the moment?

How did you have the wiring previously installed so it read the incorrect voltages? Maybe I have it hooked up similarly to how you used to have it setup. Thanks.

-Mike

 

... diode trick?... what is this?... this is the first time i have ever heard of it... anyone care to speak on it?... thanks...

 

straight from hondata's site:

Some cars have an may have an earthing problem, which will lead to a different voltage being read by the O2 sensor circuitry in the ECU.

Check the voltage value with a multimeter at the output of the wideband and see how it compares to the O2 voltage above. If there is a difference, install a diode with the diode cathode pointing to the FJO and the anode pointing to the the O2 plug (green sensor ground wire) The diode is type 1N4001, Radio Shack part # 276-1101. Thie prevents what is called a ground loop.