Eel_Dahc
Junior Member
I'm trying to figure out why I keep getting the P0052 HO2S Heater Circuit High (Bank 2, Sensor 1)
I replaced both bank 2 sensors with NGK/NGT replacements. I was getting circuit high for both but now only sensor 1 is giving the code.
I cleaned all grounds under the hood. I ohmed out the ground and I get a good ground at the O2 plug port. It's a white wire on the sensor and had me confused at first. I get get a good connection from the harness O2 plug to the C2 PCM plug for the heater. PCM Pin 17 for heater. None of the harness wires had continuity between them. 800 or so ohms maybe on 2 of them. The new sensors have 5 to 6 ohms resistance between ground and the heater wire.
I have one of those bluetooth scan tool things and I've been running an app that shows the 02 sensor levels and voltages.
I noticed that the bank 2 sensor 1 would stay at 1.27v for quite some time while the others went down fairly quickly when engine runs. All four start out at 1.27v when cold.
It does not specify if the 1.27v is for the heater or the sensor.
BTW Battery disconnected every time I disconnect or reconnect the O2 sensors. I also connect the pos and neg cables together for a bit to drain it.
I then swapped B1S1 with B2S1 cleared codes and ran it again.
I still get the code and the B2S1 still shows 1.27v longer than the others do. I am guessing that the sensor isn't heating up on it's own and voltage goes down with heat from the actual exhaust.
I haven't done it yet but I plan to cut the old sensor plug off so that I can attach my meter to the wires to test the voltage.
If it turns out that the PCm has a problem and isn't sending enough juice to the heater for that sensor, would it be wise to tap into one of the other sensors to bring the voltage up? I think it's supposed to be 12v.
Took the old sensor plug and put a light bulb on the heater wires, the bulb does not light up on B2S1 but does on B2S2. ALthough, the sensor was removed as well, may try again with the sensor attached tomorrow.
Thanks
1/31 I wired the old 02 sensors' heater control wires together and put those back in, so now 12v comes from s2 to s1. Now S1 heats up quick enough to not throw fuel trims too far out of whack. Guess I need a new PCM.
I replaced both bank 2 sensors with NGK/NGT replacements. I was getting circuit high for both but now only sensor 1 is giving the code.
I cleaned all grounds under the hood. I ohmed out the ground and I get a good ground at the O2 plug port. It's a white wire on the sensor and had me confused at first. I get get a good connection from the harness O2 plug to the C2 PCM plug for the heater. PCM Pin 17 for heater. None of the harness wires had continuity between them. 800 or so ohms maybe on 2 of them. The new sensors have 5 to 6 ohms resistance between ground and the heater wire.
I have one of those bluetooth scan tool things and I've been running an app that shows the 02 sensor levels and voltages.
I noticed that the bank 2 sensor 1 would stay at 1.27v for quite some time while the others went down fairly quickly when engine runs. All four start out at 1.27v when cold.
It does not specify if the 1.27v is for the heater or the sensor.
BTW Battery disconnected every time I disconnect or reconnect the O2 sensors. I also connect the pos and neg cables together for a bit to drain it.
I then swapped B1S1 with B2S1 cleared codes and ran it again.
I still get the code and the B2S1 still shows 1.27v longer than the others do. I am guessing that the sensor isn't heating up on it's own and voltage goes down with heat from the actual exhaust.
If it turns out that the PCm has a problem and isn't sending enough juice to the heater for that sensor, would it be wise to tap into one of the other sensors to bring the voltage up? I think it's supposed to be 12v.
Took the old sensor plug and put a light bulb on the heater wires, the bulb does not light up on B2S1 but does on B2S2. ALthough, the sensor was removed as well, may try again with the sensor attached tomorrow.
Thanks
1/31 I wired the old 02 sensors' heater control wires together and put those back in, so now 12v comes from s2 to s1. Now S1 heats up quick enough to not throw fuel trims too far out of whack. Guess I need a new PCM.
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