I have a 2001 4.7L Quad Dakota. My error codes are P0141 & P0161, O2 heater sensor circuit malfunction. The sensors have 4 wires:Blue-O2 signal, White-ground, Black1-12VDC, and Black2-heater. I pulled the sensor plug and found ground and 12VDC, but the heater line is shorted to ground (without the sensor plugged in). I read an explanation that the 141 & 161 codes mean that the heater circuit is drawing more then 2.25A, which I could believe if the heater line is shorted upstream of the sensor. When I attempt to read the resistance of the sensor heater (black to black) it appears open. Does this make sense? If the harness is shorted, I'd hate to blow $250 on two new sensors and burn them out. Does anyone have any ideas????? The truck won't pass inspection with the faults.
This ad is not displayed to registered and logged-in members. Register your free account today and become a member on Dodge Forums!
Sponsored Links
Registered users do not see this ad. Click here to register for free!
Looks by your description that you should be checking resistance between White-Ground and Black2-Heater on the sensor connector to check the heater itself.
They are not always that simple. I know for a fact that GM sensors cannot be tested this way because they are PWM heaters. Same thing, a 4 wire setup, but the 12V in and ground aren't simply just both legs of the heater resistor. The third heater wire sends a PWM signal to determine the amount of resistance that the heater resistor should produce.
It sounds like you have your hands on a service manual, follow the trouble tree.
__________________
This post may contain information to be taken lightly.
Failure to do so may cause your head to pop off. It is also recommended that this is to be taken with a sense of humor, or anything else that may help you through the day.
Thank you,
Mr. Sucks
Actually I don't have a manual...seems as though no one has made one. I have been researching the O2 sensors online through various articles. I read that the heater draws 1.5A when cold then drops to 100mA when at operating temps. I will check the current draw-I guess that would be the best indictor of whether or not the sensor heater is good. If the heater is open, there should be no current flow. I still find it odd that with the sensor removed, the heater line is shorted to ground in the harness.
The best Manual in the World for your truck can be purchased here.......1-800-890-4038.
Your manual # is 81-370-1010 for the AN Dakota.
Don't know about price and this is too early of a model for me to provide you with a copy on CD. Mine is paper.
__________________
This post may contain information to be taken lightly.
Failure to do so may cause your head to pop off. It is also recommended that this is to be taken with a sense of humor, or anything else that may help you through the day.
Thank you,
Mr. Sucks
O2 P0141 & P0161 faults
