LazLong

I just got a P0134 DTC that I want to take care of myself. ALLDATAdiy provides the diagnostic steps, which require checking the internal reistance value of the O2 sensor, however it doesn't provide any hint about how to accomplish this. From the photos/diagrams it appears the sensor's connector is shrouded so I can't get to the pins while it's coupled together, and I don't want to just stick the ice pick probes from my multimeter into the wires.

Also, it's not clear to me how I'm to measure the internal resistance of the O2 sensor. i.e. which pins I use to complete the circuit for which resistance needs to be measured.

Would someone bestow upon me their Acura lore, for I am a lowly n00b in need of guidance.

Turbonut

iTrader: (1)

I like to check the range(values) when driving/operating the vehicle, but here's one with the sensor removed.
First one I came upon on the net:
Driveway Diagnostics - Bad Oxygen Sensor - Jp Magazine

LazLong

Thank you for yor reply and the link. I too think it is better to test the sensor with the vehicle running. To that end, ALLDATAdiy has a list of value to be used for determining if the O2 sensor is faulty:

Malfunction Threshold

Malfunction determination 1
The rear A/F sensor (bank 1, sensor 1) internal resistance value is 110 ohms or more for at least 40 seconds right after the engine starts.

Malfunction determination 2

• The rear A/F sensor (bank 1, sensor 1) internal resistance value is 110 ohms or more for at least 15 seconds .
• The rear A/F sensor (bank 1, sensor 1) internal resistance value is 200 ohms or more for at least 1 second .

Driving Pattern
Start the engine, then let it idle for at least 1 minute .


I've got the diagram for both the O2 sensor and the sensor relay; I just don't know which wires to use to complete the circuit to check the resistance value.



Is it #4 WHT? Do I check by shorting #3 GRN/YEL and #4 WHT to create a circuit and measure its resistnace?

I also don't know how I'm supposed to do this with the car running as the O2 sensor connector isn't conducive to getting access to the ends and I don't want to be poking the wires with an ice pick probe. Do you have any advice?

Turbonut

iTrader: (1)

I've never checked or even inquired about an O2 resistance test, but from what I see, resistance is only checked on the heater wires, but used for testing mixture reading.

LazLong

Well, I've never done this before, so I'm just trying to do what ALLDATAdiy says. I guess I could go buy a propane torch and try the test described in the link you posted.

BTW, the image I posted of the O2 connector's pinout seems to randomly change to another graphic each time I reload the page. Something weird with the vBulletin software. I can't edit the message, so I'm just going to paste it again but use the insert image button instead of just copy-and-paste.






EDIT: There, now it seems to be loading the graphic properly.

LazLong

Maybe I'm going about this wrongly. I'm more used to computer wiring and not auto wiring. Am I supposed to pull the O2 sensor's relay and check the resistance there? Is the sole purpose of the relay to provide access to the O2 sensor's circuit so you can check the impedance without having to poke around in the wiring harness with an ice pick probe?