Hi, I have problem with calibrating wbo2 sensor. During calibration sensor gets hot and starts to calibrate then gets to 255 but obviously sensor isn't calibrated as you can see on the picture. I have two sensors and it is same thing for other one. Firmware is 1.1.96 and vems tune is latest stable.
(http://i48.tinypic.com/vxf7dj.jpg)
Does the sensor heating works? Sensor getting warm?
Quote from: GintsK on February 25, 2013, 02:15:16 PM
Does the sensor heating works? Sensor getting warm?
yes, both of them
Then you have to check wiring. And WBO2 related settings including pump zero and nernst target.
New unit? What sensor?
Wiring is ok I have checked it recently and it is vems harness. WBO2 settings are default. One sensor is slightly used other one is old three years, both are bosch lsu4 from vems shop.
How the problem starts?
There is no defaults for pump zero and nernst target.
I don't understand question, if you mean when problem started I can't tell you with certainty because a lot of parameters and firmwares changed during two calibrations.
Pump zero is 101 and nernst target is 136.
(http://i54.tinypic.com/2eydr12.png)
Sensor resistance is 142 ohm, what is normal ?
Heater resistance should be 3...6 Ohm.
This is the best and most clear guide I know of to verify your hardware in relation to the wideband controller.
http://www.vems.hu/wiki/index.php?page=GenBoard%2FManual%2FWideBandHardwareTest
Quote from: GintsK on February 26, 2013, 08:56:06 PM
Heater resistance should be 3...6 Ohm.
i meant a resistance between pin 2 and pin 6
Quote from: jrussell on February 27, 2013, 05:54:11 AM
This is the best and most clear guide I know of to verify your hardware in relation to the wideband controller.
http://www.vems.hu/wiki/index.php?page=GenBoard%2FManual%2FWideBandHardwareTest
ok, i am gonna try it
Quote from: B3mt1 on February 27, 2013, 10:56:18 AM
Quote from: GintsK on February 26, 2013, 08:56:06 PM
Heater resistance should be 3...6 Ohm.
i meant a resistance between pin 2 and pin 6
It is BOSCH factory calibration resistor. Pin 2 is not used in VEMS V3.
DVM - DVM + My values Var to Change Notes
GND pump- +4.04V Just verify
pump- pump+ 0mV pump_pw_zero WBO2 off
pump- nernst +250mV wbo2_nernst_dc_target WBO2 on |
When I lower nernst dc target to 80, value is around 120mV, when i raise nernst target voltage between pump- and nernst won't get over 250mV. Did it everything by instructions, only i didn't connect anything to heater.
Solved the problem :D
Oxidised contact on nernst pin inside vems.