Is this O2 sensor data possible?
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Lead Driver
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Is this O2 sensor data possible?
Basically, the first two on the scan tool are the "O2 sensor readings" and the 2 circles on the right are the plugs for the 2 pre-cat sensors unplugged. Unless I am misunderstanding the O2 data, I shouldnt see anything on the first two data lines while the truck is off. (The truck is turned off, key on for this picture)
When I had it in graph mode, the graph would sometimes spike and fall back down while handling the plugs still not hooked up. Does this represent a PCM issue or a wiring problem inside the harness somewhere? I did a gentlle tap test on the PCM while watching and on the wiring from the pcm to the back of the motor, where I believe these run, and nothing changed that I could observe. All engine off.
the heater current I dont understand quite so much, so if it looks erronous that I would not be surprised but I am not focused on that.
Logistics Pro
Joined: Aug 2014
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If they are unplugged, your going to get phantom readings. Pretty sure if the circuit is open(unplugged) you will get erroneous results.
You should put your vehicle year, model, engine and trans in your signature, so we know what you are working on.
You should put your vehicle year, model, engine and trans in your signature, so we know what you are working on.
Logistics Pro
Joined: Aug 2014
Posts: 3,554
Likes: 848
To answer your question, Yes, the data is possible, but no your not testing it correctly.The HO2S heater circuit is monitored by detecting proper voltage change as the heater is turned on and off.
You have it unplugged, it will fail.
Also, input is required from the ECT, IAT, MAF, and CKP sensors to activate the HO2S Monitor. The Fuel System Monitor and Misfire Monitor must also have completed successfully before the HO2S Monitor is enabled. Some of the HO2S Monitor checks are also performed during on demand self-test.
What is the issue your trying to solve?
You have it unplugged, it will fail.
Also, input is required from the ECT, IAT, MAF, and CKP sensors to activate the HO2S Monitor. The Fuel System Monitor and Misfire Monitor must also have completed successfully before the HO2S Monitor is enabled. Some of the HO2S Monitor checks are also performed during on demand self-test.
What is the issue your trying to solve?
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