not activity on bank 1 and bank 2
Super Member
Joined: Jan 2004
Posts: 538
Likes: 2
From: Silicon valley
Audi C7.5 S6
Sounds like something wrong with the O2 wiring harness or connectors on the way to the ECU, either an open or short. If it was totally open, I would expect O2 heater codes also.
Normaly, when opening properly. the signal for the O2 bounces between 100mV & 900mV. If it was always high or always low, then it would be considered not responding or the air would be continuously either too much oxygen or too little. This is not likely if the engine runs ok.
The other possibility, although not likely is the O2 inputs (or connector) to the ECU is bad.
Here is some more info:
Faults at the O2 sensor can be detected by means of the O2 sensor signal.
Defined limit values must be maintained for the O2 sensor voltage, the duration of the period and for the sensor status change.
The O2 sensor signal has a steep voltage jump (at lambda=1) at the transition from a rich (A) to a lean mixture (B). This property is utilized for the lambda closed-loop control.
Things that are monitored:
Duration of sensor state change for lean-rich transition
Duration of sensor state change for rich-lean transition
Duration between sensor state change
Threshold for rich range (e.g. greater than 475 mV)
Threshold for lean range (e.g. less than 425 mV)
Normaly, when opening properly. the signal for the O2 bounces between 100mV & 900mV. If it was always high or always low, then it would be considered not responding or the air would be continuously either too much oxygen or too little. This is not likely if the engine runs ok.
The other possibility, although not likely is the O2 inputs (or connector) to the ECU is bad.
Here is some more info:
Faults at the O2 sensor can be detected by means of the O2 sensor signal.
Defined limit values must be maintained for the O2 sensor voltage, the duration of the period and for the sensor status change.
The O2 sensor signal has a steep voltage jump (at lambda=1) at the transition from a rich (A) to a lean mixture (B). This property is utilized for the lambda closed-loop control.
Things that are monitored:
Duration of sensor state change for lean-rich transition
Duration of sensor state change for rich-lean transition
Duration between sensor state change
Threshold for rich range (e.g. greater than 475 mV)
Threshold for lean range (e.g. less than 425 mV)
Last edited by m444; Nov 15, 2006 at 12:40 PM.
Super Member
Joined: Jan 2004
Posts: 538
Likes: 2
From: Silicon valley
Audi C7.5 S6
There you go, I was expecting heater codes.
P0141 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0161 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
This means all the lines to the O2 sensor are not doing what they should.
http://www.autoshoppingcenter.com/OB...ublecodes.html
P0141 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0161 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
This means all the lines to the O2 sensor are not doing what they should.
http://www.autoshoppingcenter.com/OB...ublecodes.html
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Super Member
Joined: Jan 2004
Posts: 538
Likes: 2
From: Silicon valley
Audi C7.5 S6
Check wiring harness and connectors
Check your O2 wiring harness and connectors, from the O2 sensor up to the connection on the ECU. Something is probably open or shorted or mis-wired.
From these older posts, it would appear that you may have been playing with the O2 wires?
https://mbworld.org/forums/showthrea...28#post1788028
https://mbworld.org/forums/showthrea...80#post1788380
You can get wiring info at, Alldatadyi, it is $24.95 for a one year subscription:
http://www.alldatadiy.com/
Using the O2 spacers is definitely better than trying to use a simulator.
From these older posts, it would appear that you may have been playing with the O2 wires?
https://mbworld.org/forums/showthrea...28#post1788028
https://mbworld.org/forums/showthrea...80#post1788380
You can get wiring info at, Alldatadyi, it is $24.95 for a one year subscription:
http://www.alldatadiy.com/
Using the O2 spacers is definitely better than trying to use a simulator.
Guest
Posts: n/a
i did install o2 simulators but i spliced the wires on the side of the o2 sensor and ever since i have these codes pop up. i went and changed my o2 senors thinking it was them and now still the same. do you think the wires are bad? or did i short the pc or a relay?
Super Member
Joined: Jan 2004
Posts: 538
Likes: 2
From: Silicon valley
Audi C7.5 S6
On the O2 sensor:
View facing O2 connector, with flat at bottom, of electrical connection for O2sensor, starting with (1) at the lower right, running
counterclockwise, the pin out is:
1 Sensor heater
2 Sensor heater ground
3 O2 sensor signal ground
4 O2 sensor signal
If you disconnect the O2 sensor and read the voltage for the pins of the wiring harness O2 connector, with a DVM;;;
With the engine cold and running, you should see some voltage across the heater pins, probably around 12V. The O2 sensor signal pins should have about 0.47V across them for the read back signal, see below.
""The ground for the sensor signal is increased to approx. +0.268 V compared to the general vehicle ground e.g. at the ME 2.1 control unit. In the event of a short circuit of the sensor signal to ground, the ME control unit thus switches the lambda control to open-loop mode (average lambda value). This prevents a high fuel consumption.
The analysis circuit for the O2 sensor signal outputs a so-called sensor back voltage of approx. 0.470 V. If the O2 sensor is cold, the sensor internal resistance is so high that the O2 sensor voltage is initially equal to the backvoltage irrespective of the mixture composition.
The backvoltage at the ME control unit can be measured to the sensor ground if the O2 sensor is disconnected. ""
If this all comes up dead, then either the wiring harness is toast or the ECU is toast.
View facing O2 connector, with flat at bottom, of electrical connection for O2sensor, starting with (1) at the lower right, running
counterclockwise, the pin out is:
1 Sensor heater
2 Sensor heater ground
3 O2 sensor signal ground
4 O2 sensor signal
If you disconnect the O2 sensor and read the voltage for the pins of the wiring harness O2 connector, with a DVM;;;
With the engine cold and running, you should see some voltage across the heater pins, probably around 12V. The O2 sensor signal pins should have about 0.47V across them for the read back signal, see below.
""The ground for the sensor signal is increased to approx. +0.268 V compared to the general vehicle ground e.g. at the ME 2.1 control unit. In the event of a short circuit of the sensor signal to ground, the ME control unit thus switches the lambda control to open-loop mode (average lambda value). This prevents a high fuel consumption.
The analysis circuit for the O2 sensor signal outputs a so-called sensor back voltage of approx. 0.470 V. If the O2 sensor is cold, the sensor internal resistance is so high that the O2 sensor voltage is initially equal to the backvoltage irrespective of the mixture composition.
The backvoltage at the ME control unit can be measured to the sensor ground if the O2 sensor is disconnected. ""
If this all comes up dead, then either the wiring harness is toast or the ECU is toast.
Guest
Posts: n/a
let me start with thanking you for all your help.
today i got some time to hook up a obd2 pc
and check the acitvity on the o2 sensors and i got
02s11 read out any were from .080-.745
02s12 .150-.445
02s21 .195-.740
02s22 .475 and all up and down
i got 12v on both senors bank 1 and bank 2
i also got a power on one other wire 2
the other 2 wires are dead no power.
also these are inc. catalyst mon, evap system mon, sec air system, oxygen sensor mon., and oxygen sens htr.
this was after i cleared the check engine light
i hope with this you can help me out. i hope its not my ecu. must be very expensive.
today i got some time to hook up a obd2 pc
and check the acitvity on the o2 sensors and i got
02s11 read out any were from .080-.745
02s12 .150-.445
02s21 .195-.740
02s22 .475 and all up and down
i got 12v on both senors bank 1 and bank 2
i also got a power on one other wire 2
the other 2 wires are dead no power.
also these are inc. catalyst mon, evap system mon, sec air system, oxygen sensor mon., and oxygen sens htr.
this was after i cleared the check engine light
i hope with this you can help me out. i hope its not my ecu. must be very expensive.
Super Member
Joined: Jan 2004
Posts: 538
Likes: 2
From: Silicon valley
Audi C7.5 S6
These seem like the first O2 sensors for each side, sensor 1, bank 1 & 2
which seem like they are working OK.
"02s11 read out any were from .080-.745"
"02s21 .195-.740"
These appear to be the sensors after the first cats
This is lean, too much O2, "02s12 .150-.445"
This one is not right
The threshold of rich is 0.470, "02s22 .475 and all up and down"
It should bounce from around 0.100V or 0.200V to around 0.900V or 0.800V
If the O2 sensor is not up to temp and not working the voltage should be about 0.470V (ECU read back voltage).
P0105 = Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
This would mean the manifold vacuum is incorrect. Could be cause by a faulty vacuum hose.
which seem like they are working OK.
"02s11 read out any were from .080-.745"
"02s21 .195-.740"
These appear to be the sensors after the first cats
This is lean, too much O2, "02s12 .150-.445"
This one is not right
The threshold of rich is 0.470, "02s22 .475 and all up and down"
It should bounce from around 0.100V or 0.200V to around 0.900V or 0.800V
If the O2 sensor is not up to temp and not working the voltage should be about 0.470V (ECU read back voltage).
P0105 = Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
This would mean the manifold vacuum is incorrect. Could be cause by a faulty vacuum hose.
Super Member
Joined: Jan 2004
Posts: 538
Likes: 2
From: Silicon valley
Audi C7.5 S6
It appears that the back two O2 sensors, after the front cat, are not giving proper readings. Read the note above, again.
There are four O2 sensors. All four need to work properly. All four need to have power, to their heaters, when the engine is cold. The O2 sensor needs to be 300 degrees, before it works, so cold start, needs the heaters.
There are four O2 sensors. All four need to work properly. All four need to have power, to their heaters, when the engine is cold. The O2 sensor needs to be 300 degrees, before it works, so cold start, needs the heaters.
