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My car has been throwing both these codes. Showed up at the same time. its a high voltage code to the rear o2 sensor. I highly doubt both o2 sensors went at the exact same time. Any other ideas on what the possible problem could be?
 

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This engine light coming out is really driving me nuts. I've checked for exhaust leaks I had two so i fixed them. I replaced the o2 sensors on both side. I'm still getting the same two codes. Anyone know what the voltages are supposed to be when i check the sensor signal at the plug and what the voltage should be at the plug for the sensor heater? I know my cats are gone now but they were with the headers i used to have on there too. i run o2 standoffs and I never got a code before. I'm really hoping something isn't screwy in the pcm with this problem.
 

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Both error codes are for sensors located after the converters.

A high voltage reading comes from a lack of oxygen in the exhaust gas. A rich mixture consumes more oxygen and at the sensor this causes an oxygen demand and the demand causes voltage to build up. (A lean mixture, with an excess of oxygen, causes a low voltage level as there is an excess of oxygen in the exhaust gas.)

For both errors, possible causes:
Bad O2 sensor.
Bad O2 sensor heater circuit (bad sensor).
Fuel pressure too high.
Engine coolant temperature sensor bad.
Bad O2 sensor wiring.
Bad engine controller.

For both sensors to "fail" concurrently suggests the problem is not with the sensors but is something common to both. Thus fuel pressure or a bad coolant temperature sensor are suggested.

Under normal operation the #2 sensor voltage should rise and fall sort of in sync with the very obvious rise and fall of the #1 sensor voltage. The #2 sensor voltage though doesn't vary by much. Mostly the voltage reading wants to be in the 0.6V to 0.7V range indicating a lack of oxygen in the exhaust. In this case the assumption is the excess oxygen (evident from the voltage reading of the #1 sensor) is being consumed in the converter.

(By way of contrast, the #1 sensor voltage level swings from a low of 0.2V (or bit lower) to 0.7V (or a bit higher). This is for narrow band sensors, 0V to 1V. )

I have no O2 diagnostic experience with Dodge engines. For other engines, my Actron OBD2 code reader/data logger would give me access to some O2 sensor tests the engine controller supported and I could run these tests and in some cases the test results would clearly indicate a bad sensor, or sensors.

It is likely the Dodge engine controller supports some of the same O2 sensor tests and with a suitable OBD2 code reader/data logger/data viewer you could run these tests. You could of course use this tool to view the #1 and #2 sensor voltages in real time.

But as I touched upon above while the sensor readings indicate a problem the problem may not be with the sensors but something else.

And you can also view the engine coolant temperature in real time. If this is low even if intermittently this can be a problem.

Need to mention some things regarding O2 sensors. Do not use anti-seize on the threads. Do not touch the tips. Do not clean the sensors. Do not spray any electrical contact cleaner on the electrical contacts. (Some sensors "breathe" via their wiring from the sensor to the connector.) Do not check resistance of the tip to ground. You are allowed to check continuity of the sensor's heating circuit.

To kind of bring this to a close, you need to check the coolant temperature, fuel pressure, and be sure to check all the wiring. My usual course of action is to check/eliminate the easier stuff first, like the coolant temperature and wiring, before messing with fuel system to take a fuel pressure reading. Any time one messes with the fuel system there's always the risk of a fire.
 
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