O2 sensor heater circuit malf.

there are about a dozen O2 sensor codes. Tell us which one you have

O2 sensor's don't have a fuse , except for the heater circuit. PCM - engine computer supply's five volt's , signal return and ground . All are connected at the PCM . The fuse's you are calling O2 sensor fuse's are for the heater circuit . The PCM controls the O2 heater circuit by pulse width modulation ,do you know what that is .There is a transistor inside the PCM that toggles the ground on an off to control the heater circuit . Unless you know automotive electrical circuit testing an testing PCM input's an outputs ,your best bet , take your vehicle to a qualified repair shop .

Pulse width modulation Pulse width modulation

Here's a link for codes P0446,P0443. https://www.obd-codes.com/p0446 Here's the link for P0403. P0403 Exhaust gas recirculation EGR circuit malfunction Here's code P0135 P0135 OBD II Trouble Code O2 Sensor Heater Circuit Malfunction Bank 1... Here's code P0141 P0141 OBD II Trouble Code O2 Sensor Heater Circuit Malfunction Bank 1... Here's code P0155. P0155 OBD II Trouble Code 02 Sensor Heater Circuit Malfunction Bank 2... Here's the last code.yay P0161. P0161 OBD II Trouble Code HO2S Heater Circuit Malfunction Bank 2 Sensor 2... The last 3 codes might just be one sensor.

If the sensors were replaced an DTC'S come back has to be a wiring problem or PCM ,
The ECM detects that the HO2S heater low control circuit voltage is between 2.6-4.6 volts when the heater is commanded OFF, indicating an open HO2S heater circuit.
Is the fuse open?
All four codes refer to the heating element circuit ! there is a relay in the under hood fuse box that supplies B+ voltage to the O2 sensor heating elements . I would change that or test the relay , videos on you tube on testing relays .
MAIN Relay
--
LO SPEED Relay, HI SPEED Relay, S/P FAN Relay, PRE O2 Fuse, IGN-1 Fuse, ECM Fuse, POST O2 Fuse, and INJ Fuse
Also check
POST O2 Fuse
10 A
HO2S Bank 1 Sensor 2 and HO2S Bank 2 Sensor 2
PRE O2 Fuse
10 A
Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 and HO2S Bank 2 Sensor 1

Did you replace the right one ? This code does not necessarily mean the O2 sensor is bad . The code description say O2 heater " CIRCUIT " bank 1 sensor 2 Did you check the wiring , the fuse ?
P0141 - O2 Heater Circuit (Bank 1, Sensor 2) Description: See the description for DTC P0135. Possible Causes: See the possible causes for DTC P0135. Diagnostic Aids: See the diagnostic aids for DTC P0135. Application Key On Engine Off Key On Engine Running Continuous Memory All GO to Pinpoint Test DW . P0135 - O2 Heater Circuit (Bank 1, Sensor 1) Description: During testing the heated oxygen sensor (HO2S) heaters are checked for open and short circuits and excessive current draw. The test fails when the current draw exceeds a calibrated limit or an open or short circuit is detected. Possible Causes:

• Vacuum hose disconnected on exhaust gas recirculation (EGR) system module (ESM) applications
• Short to VPWR in the harness or HO2S
• Water in the harness connector
• Open VPWR circuit
• Open GND circuit
• Low battery voltage
• Corrosion or incorrect harness connections
• Damaged HO2S heater

Diagnostic Aids: Check the HO2S electrical connector for damage, corrosion, and water intrusion.
Damaged HO2S heater. Application Key On Engine Off Key On Engine Running Continuous Memory All GO to Pinpoint Test DW .

Trouble Code: P0060 This HO2S Heater they speak about is the oxygen sensors, it has two of them.Bank 1 is cyls. 1,2,3 from the front of the car 1 is in the back bank 2 is the front 4,5,6. You will find an o2 sensor screwed into each exhaust manifold.

HO2S Heater Resistance (Bank 2, Sensor 2)
Possible Causes:


VPWR circuit open HO2S heater circuit open HO2S heater circuit short in the harness Damaged HO2S heater

Hi there:

This fault code refer at Oxygen O2 Sensor Circuit Low Voltage (Bank 2, Sensor 2), and basically means the PCM detected either an excessive current draw, or an open or short in the circuit powering the oxygen sensor's heater circuit. This is in reference to the Heated Oxygen Sensor (2) located rear of catalytic converter (Bank 2).

A code P0161 may mean that one or more of the following has happened:

• HO2S heater power circuit open
• HO2S heater ground circuit open
• HO2S signal tracking (due to oil or moisture in the connector)
• HO2S is damaged or has failed PCM has failed

Possble soutions:

• Replace HO2 Sensor
• Repair open or short in power circuit
• Repair open or short in ground circuit
• Repair damaged connector due to tracking

Use this Ford diagram about O2 sensor location...




O2 Sensor 2 Bank 2 = HO2S 2/2 (zoom image link)

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P0134....O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)

P0135....O2 Sensor Heater Circuit (Bank 1 Sensor 1) heater in the O2 sensor has packed up first sensor before the cat

It basically means the PCM detected either an excessive current draw, or an open or short in the circuit powering the oxygen sensor's heater circuit. This is in reference to the Heated Oxygen Sensor (2) located rear of catalytic converter (Bank 2).

A code P0161 may mean that one or more of the following has happened:
· HO2S heater power circuit open
· HO2S heater ground circuit open
· HO2S signal tracking (due to oil or moisture in the connector)
· HO2S is damaged or has failed PCM has failed

Possible Solutions
· Replace HO2 Sensor
· Repair open or short in power circuit
· Repair open or short in ground circuit
· Repair damaged connector due to tracking

Hello..
Code 21: Is an oxygen sensor Code 54: Is a crank positioning sensor.
Hope this helps!