Open Air readings

Support forum for the Lambda Shield designed to connect Bosch LSU 4.9 wideband oxygen sensors to Arduino projects.
Groopan
Posts: 5
Joined: 11 Feb 2019 02:41

Re: Open Air readings

Post by Groopan » 12 Feb 2019 10:47

blacksheepinc wrote:
14 Jan 2019 09:03
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
Posts: 3
Joined: 14 Jan 2019 08:56

Re: Open Air readings

Post by blacksheepinc » 12 Feb 2019 14:24

Groopan wrote:
12 Feb 2019 10:47

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
Posts: 5
Joined: 11 Feb 2019 02:41

Re: Open Air readings

Post by Groopan » 12 Feb 2019 16:05

blacksheepinc wrote:
12 Feb 2019 14:24
Groopan wrote:
12 Feb 2019 10:47

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
Posts: 5
Joined: 11 Feb 2019 02:41

Re: Open Air readings

Post by Groopan » 21 Feb 2019 01:23

elmo0104 wrote:
24 Nov 2018 17:20
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
Posts: 1
Joined: 06 Jun 2019 06:10

Re: Open Air readings

Post by shambu31 » 06 Jun 2019 10:27

Excellent thread..!!!

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