Author Topic: Wideband input stopped working, any ideas?  (Read 7737 times)

Offline DButters

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Wideband input stopped working, any ideas?
« on: December 29, 2008, 02:32:09 am »
Hi all,
I have had my VEMS unit running for over 6 months now, and noticed that some time in the last 2 weeks the wideband reading has become stuck at 14.2 (or similar base value depending on calibration values I set).
The only thing I changed in that time was to add a tacho output on one of the misc channels. I measured all voltages at the sensor according to the user guide and they match exactly, and the sensor heater is working.

Any likely places to look for a problem here? Any more info needed to help diagnose the problem?

Thanks in advance!



Offline GintsK

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Re: Wideband input stopped working, any ideas?
« Reply #1 on: December 29, 2008, 03:15:30 am »
And what about O2 sensor itself?

Offline DButters

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Re: Wideband input stopped working, any ideas?
« Reply #2 on: December 29, 2008, 03:50:58 am »
I will have to pull out my old AFR gauge to double check, but it is less than 2 months old and the vehicle has just been dyno tuned so im not pouring fuel into it :). I will update that status, but in the mean time is there any way to test a reading without a sensor? no resistor / voltage divider combination we can use to fake any reading?

Offline Bat

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Re: Wideband input stopped working, any ideas?
« Reply #3 on: December 29, 2008, 04:09:08 am »
Hi,
Check the 12v feed to the sensor.
Cheers,
Gavin :)
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Offline Denmark

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Re: Wideband input stopped working, any ideas?
« Reply #4 on: December 29, 2008, 10:10:25 pm »
I have had 2 sensors that have failed within 6month, on 2 different cars, one was showing values all over the place, and shifting fast, and the other was just showing lambda 2.67 all the time,
Both was working great with new sensors


/Skassa
working on the boxer

Offline DButters

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Re: Wideband input stopped working, any ideas?
« Reply #5 on: December 30, 2008, 12:04:35 am »
Thanks for this info - I will check it out shortly. is there a fixed value that the wideband chip should give us back (i.e. a fixed reading we should see) when the sensor is disconnected and the ECU is working properly? Or does it just hang on to the last good reading?