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post #6 of (permalink) Old 01-26-2011, 01:02 PM
Rickl
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Quote:
Originally Posted by wake_100
you mean multiple sensors? with the 2.4 there is only 2 sensors. I checked the sensors for resisitance and they check okay as per service manual but we'll say something is on sensor one (upstream) that wouldnt change the value of the resistance I think. I think if sensor one was coated in soot it would make it rich making sensor two high voltage?
Your O2 sensors are fed by two different circuits.

The first circuit is the heater circuit, and the other is the O2 detection circuit.

O2 sensors only work properly when they reach a certain temperature. In the old days they didn't work until the exhaust manifold was hot enough to provide the proper temperature. In today's cars they use heated sensors. The ECM provides a voltage solely to heat up the sensors to provide O2 data sooner than the old time technology. Faults with the heater circuit will normally give a different diagnostic code than the one you are getting.

The second circuit supplies battery voltage on one wire, and depending on what the O2 levels are, the sensor sends varying voltage back on a second wire. The code you are getting implies that this return voltage is higher than anything that should be normally seen. Therefore, either your sensor is defective, and is sending the battery voltage back on the signal wire, or a short somewhere in the harness is sending voltage back to the signal terminal of the ECM. The diagnostic charts in the PDF will help you determine where the problem is.


Quote:
Originally Posted by wake_100
I am wondering about my vacuum system in it to. I can sit at a stop light, and just stretch my leg pressing the brake pedal and I can set of the stability control. it'll beep and the light of the car with skid marks under it will light up. can reproduce it 100%

That is you HAC feature. Have a look at http://rav4world.com/forums/viewtopic.php?t=14769
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