You are watching: Ho2s heater control circuit high (bank 1 sensor 1)
The heater temperature is derived by measure up the heater resistance and calculating the heater temperature using the resistance versus temperature characteristic. In order to measure up the heater temperature, the transistor that controls the heater is momentarily disabled and current is passed with a precision feeling resistor linked is collection with the heater element. The voltage drop across the sense resistor provides the relationship to current which amounts to a temperature value. As soon as the temperature is acquired, the sense current is turned off and normal operation is restored.When monitored upstream O2 Sensor Heater Circuit short DTC room not active, battery voltage between 10.4 and also 15.75 volts, auto Shutdown Relay (ASD) is energized. Set condition the O2 Sensor Heater facet resistance is above the minimum agree threshold. Default action, mulfunction Indicator lamp (MIL) light will illuminate.
O2 Sensor 1/1 Heater manage circuit open up or high resistance.O2 Sensor 1/1 Heater ground circuit open up or high resistance.O2 Sensor 1/1 Heater control circuit shorted to voltage.O2 sensor 1/1.Powertrain manage Module (PCM).
See more: How To Write 90% As A Decimal S, Fractions And Percentages, What Is 90 Percent As A Decimal
Step 1. Check for an active DTCIf P0688-Auto Shutdown relay feeling circuit low, has set along with any of the O2 Sensor Heater circuit High DTC, every one of the O2 sensor heater regulate circuits should be checked for a quick to battery voltage. Test drive or operate the automobile in accordance with the as soon as monitored and collection conditions. With the scan tool, check out DTC.Is the DTC active or pending ?Yes, walk to action 2.No, execute the PCM intermittent condition.Step 2. Inspect the O2 Sensor 1/1 Heater elementTurn the ignition off. Permit the O2 Sensor come cool down to room temperature. Disconnect the O2 Sensor 1/1 harness connector, measure the resistance throughout the O2 Sensor 1/1 Heater element between the O2 Sensor 1/1 Heater manage terminal and the O2 Sensor 1/1 Heater floor terminal in ~ the component. O2 Sensor 1/1 Heater element resistance values have to be measure at21.1°C (70°F). The resistance value will vary with various temperature values.Is the O2 Sensor 1/1 Heater facet resistance in between 2.0 and also 35.0 Ohms ?Yes, walk to action 3.No, verify that there is an excellent pin come terminal call in the O2 Sensor 1/1 and Powertrain manage Module Connectors. If no troubles are found, replace the O2 Sensor 1/1. Perform the Powertrain confirmation Test.Step 3. Check the O2 Sensor 1/1 Heater control circuitTurn the ignition on. Make certain the check light is probing the circuit before actuating the Heater check or a DTC may collection and not enable the actuation. Using a 12 volt test light linked to ground, probe the O2 Sensor 1/1 Heater regulate circuit in the O2 Sensor 1/1 harness connector. With the scan tool, actuate the O2 Sensor 1/1 Heater test through the sensor exploit connector quiet disconnected.The check light need to be illuminated and also bright proportional come the preferably duty cycle permitted by the scan tool. Because that example, if the scan tool allows 100% actuation, the brightness have to be together a direct link to the battery. If the scan tool allows a maximum25% actuation, the brightness should be25% together bright as a direct link to the battery.Does the test light illuminate during actuation ?Yes, go to step 4.No, go to action 5.Step 4. Inspect the O2 Sensor 1/1 Heater ground circuit for an open or high resistanceTurn the ignition off, measure up the resistance between an engine ground and also the O2 Sensor 1/1 Heater floor circuit at the O2 Sensor harness connector.Is the resistance listed below 3.0 Ohms ?Yes, verify the there is great pin come terminal call in the O2 Sensor 1/1 and also Powertrain manage Module connectors. If no problems are found, replace the O2 Sensor. Perform the perform thePowertrain verification Test.No, repair the O2 Sensor 1/1 Heater soil circuit for an open up or high resistance.Step 5. Check the O2 Sensor 1/1 Heater control circuit for a short to voltageDisconnect the PCM harness connector, check for continuity in between the O2 Sensor 1/1 Heater control circuit and also other circuits at the PCM exploit connector.Is there continuity between the O2 Sensor 1/1 Heater control circuit and any other circuit ?Yes, fix the O2 Sensor 1/1 Heater regulate circuit for a short to the circuit that confirmed continuity.No, go to action 6.Step 6. Check the O2 Sensor 1/1 Heater manage circuit for an open up or high resistanceTurn the ignition off, measure the resistance the the O2 Sensor 1/1 Heater control circuit between the O2 Sensor harness connector and also PCM harness connector.Is the resistance listed below 3.0 Ohms ?Yes, go to action 7.No, repair the O2 Sensor 1/1 Heater control circuit for an open up or high resistance.Step7. Examine related PCM and also component connections