Open Air readings

[Groopan]

Hello Christian,

Actually I have something similar problem.
After heating phase(sensor gets hot also), it stops with error message 0xE8FF.
Also, if I modify the code it turned out, the the calibrations values are "normal" Ur=173, Ua=303, however when it exists from calibration mode, Ur is around 55-56. And does not change, it is stucked.
I have a genuine Bosch sensor.

BR
Mark

Hey blacksheepinc

I have a similar problem my heater Ur value goes under 100 and the shield reads 21%o2 then if fluctuates to 174 ur and the readings go to 12%o2 and just bounce between to two values I am trying to figure out what's wrong if you make headway let me know. With the sensor disconnected I get the ur reading to be 870

[blacksheepinc]

Hey blacksheepinc

I have a similar problem my heater Ur value goes under 100 and the shield reads 21%o2 then if fluctuates to 174 ur and the readings go to 12%o2 and just bounce between to two values I am trying to figure out what's wrong if you make headway let me know. With the sensor disconnected I get the ur reading to be 870

Hi

Haven't figured out yet. I am not measuring afr value, without properly heated sensor is pointless.
I've made two boards, I have more bosch ICs. Checked the schematic multiple times.
I believe the sensor is faulty. But it is really expensive in Hungary, dont really want to buy another one, especially the one I have is basically brand new.
The other cause might be the necessity of a low pass /slew rate filter for UR and UA.
The cj125board for rusefi has it.
*edit*
All my cj125 ICs are from aliexpress but different seller. Might be counterfeit chips? What about your setup?

[Groopan]

Hey blacksheepinc

I have a similar problem my heater Ur value goes under 100 and the shield reads 21%o2 then if fluctuates to 174 ur and the readings go to 12%o2 and just bounce between to two values I am trying to figure out what's wrong if you make headway let me know. With the sensor disconnected I get the ur reading to be 870

Hi

Haven't figured out yet. I am not measuring afr value, without properly heated sensor is pointless.
I've made two boards, I have more bosch ICs. Checked the schematic multiple times.
I believe the sensor is faulty. But it is really expensive in Hungary, dont really want to buy another one, especially the one I have is basically brand new.
The other cause might be the necessity of a low pass /slew rate filter for UR and UA.
The cj125board for rusefi has it.
*edit*
All my cj125 ICs are from aliexpress but different seller. Might be counterfeit chips? What about your setup?

I used the schematic to make my board also but I think there are a few things missing from the schematic
The mosfet driver chip is not grounded . I had issues with that . I also had grouning issues so I made a better PCB with grounding planes. Have u tried the old code that comes with the WIN GUI.

https://drive.google.com/file/d/1bu97MODRdbmzaxTSO8Vzaq_t9g63Sz4L/view?usp=drivesdk

Shoot me a email at g.roopan@gmail.com if i find the problem I will message you here. My cj125 are off AliExpress also and they work fine . My first design had a poor grounding plane my second design the planes were improved . And the result was better but with the same problem. As you with ur.

[Groopan]

Hi

I'm new here. I've made my own shield based on bylund information. It works but have some question- in open air a have a 20% content of oxygen. Most of resistors from schematic was 0.1% of precysion (not sure how to explain this value. I hope U anderstand).
Is this normal? I have bosch sensor but not new- can this be a problem?

Elmo0104 please send a email address I have some questions about your setup for the o2 shield. My email is g.roopan@gmail.com.

[shambu31]

Excellent thread..!!!