I checked with my multimeter this afternoon, and only 3.6V was being supplied to the both sensor heater from the car, while the engine running.
Technical O2 lambda sensor replacing
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Technical O2 lambda sensor replacing
I checked with my multimeter this afternoon, and only 3.6V was being supplied to the both sensor heater from the car, while the engine running.
What could it mean?
I suspect both will measure right. Its hard to get a Good contact between the multi meter probes and the pins in the connect.
If the are both good it will almost certainty be a damaged wire.
If one is intact faulty I doubt there will be any other fault. Maybe one of the new sensors is fail on fit or the code isn't clearing correctly
That readings are from the old sensors, and I double checked with thin needle like probes when they were taken out.
Now, the car has both brand new sensors installed, and they are both OK. The top one reads 6 ohms and bottom one reads 7 ohms.
But the voltage from the car to the sensors are only 3.6V. I am not sure if this is OK. I was guessing they must be 12V to work properly?
With the new sensors put in, the computer plug in reading is still showing P0135 code, which is exactly same as before with the old sensors.
Is the fault caused by the input voltage being too low? Or like my friend said, does the car needs to be reset and clear the code by the computer in the garage?
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Its unusual to get two faults at the same time. Not impossible but less likely.
The voltage path is cut by the ECU if a fault code is present.
Because its cut at the negative end its possible there's enough leaking through the meter itself to show some residual volts
Are you near Cheshire ?
Try clearing the code, disconnect the battery for a bit then try measuring the volts before the engine check light comes back
Ahhh ... because of the fault code P0135, ECU has cut the voltage to 3.6V from 12V? making them further not working? So, the ECU monitors and controls the heater supply voltage?
Yes, I have disconnected the battery for over an hour, and restarted the car, read the code, the code came back again.
Checked out the heater supply voltage to the newly installed O2 sensors, and confirmed they are both 3.6V fluctuating from 0.5 - 3.6V on the multimeter while the engine is running.
We are in near Glasgow area, so Cheshire is a bit too far for taking the car to .
Yes, I have disconnected the battery for over an hour, and restarted the car, read the code, the code came back again.
Checked out the heater supply voltage to the newly installed O2 sensors, and confirmed they are both 3.6V fluctuating from 0.5 - 3.6V on the multimeter while the engine is running.
We are in near Glasgow area, so Cheshire is a bit too far for taking the car to .
Correct. They are around 2 Amps normally.
The ECU
1) Times them. They are only powered at the beginning to speed up process of getting them working
2) Protects the electronics by shutting them down if a fault is found
It sounds like the Catch 22 situation with this car then,
Without right heater supply voltage 12V, the sensors will not function correctly.
While the sensors are not functioning correctly, the ECU will not supply the correct heater supply voltage.
One of the cables runs across the top of the join between the gearbox and engine
Its covered with a Black pipe with a slit down it and tapped at the end
If you carefully slit the tape and pull the wires out of the tube.
The run each wire between your finger and thumb should be uniform thickness. If they have been pinched you will feel it.
Its covered with a Black pipe with a slit down it and tapped at the end
If you carefully slit the tape and pull the wires out of the tube.
The run each wire between your finger and thumb should be uniform thickness. If they have been pinched you will feel it.
Would it be possible to get a photo for the cable, where it connects to at the car end? I tried to look for them in the car, but they seem disappearing into the dip couldn't trace them.
A good photo could be a great help. Or even drawings or diagram. Would the FIAT PANDA Manual have it?
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Find the top end of the Lambda wires and run a jump wire to the sensor. If it now works, you know the cable is damaged.
A great idea !!!
As long as it is 12V supply to the heater, the sensors will work if they are functional state, and the answer is the cable is the problem. Thanks.
Just to confirm, of the 2x white wires to the sensor in the clip of the sensors, which one is + and which - ? Would the polarity matter when supplying 12V to them?
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There should be a connector further up near or at the ECU where you can measure the voltages. If not you'll have to use the pin contact method. 12V for the heater can come from any 12V supply.
This might be helpful.
https://www.ebay.co.uk/itm/UNIVERSAL-4-WIRE-OXYGEN-LAMBDA-SENSOR-O2-SENSOR-FOR-FIAT-FORD-/230618334846
This might be helpful.
https://www.ebay.co.uk/itm/UNIVERSAL-4-WIRE-OXYGEN-LAMBDA-SENSOR-O2-SENSOR-FOR-FIAT-FORD-/230618334846
This post contains affiliate links which may earn a commission at no additional cost to you.
to the coil, incoming, for the relay housed inside the engine compartment junction unit B001;
The engine management control unit provides a negative signal, at pin 62 connector B, to the relay T09 coil output.
When energized, the relay provides a direct battery power supply:
to the Lambda sensors K017 and K018 (at pins 4 respectively);
The engine management control unit provides a negative signal, at pin 62 connector B, to the relay T09 coil output.
When energized, the relay provides a direct battery power supply:
to the Lambda sensors K017 and K018 (at pins 4 respectively);
What are we trying to achieve. These are two new O2 sensors. It would be very unlucky to have three faulty
Not sure how wise it is to add a 12v supply when it is potentially faulty and connected to the ECU
There is only a handful of possibilities to check. A multi meter is the correct tool for the job
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D097B no idea where this is.
I appears to be some kind of jumper bridge that connects both sensors to one 12V line
I am out all tomorrow. I will try and get a Good look at my car the next day if you haven't got anywhere
I appears to be some kind of jumper bridge that connects both sensors to one 12V line
I am out all tomorrow. I will try and get a Good look at my car the next day if you haven't got anywhere
if you can find this
http://4cardata.info/elearn/169/2/2009000/2000901/2001393/169003136
Pin 1,2,3 should be live all the time with the ignition on
No 12V on 1 would mean the problem is around the fuse box.
http://4cardata.info/elearn/169/2/2009000/2000901/2001393/169003136
Pin 1,2,3 should be live all the time with the ignition on
No 12V on 1 would mean the problem is around the fuse box.
