DTC P0030-P0032
Diagnostic Instructions
DTC Descriptors
| DTC P0030 00: HO2S Heater Control Circuit
Sensor 1 |
| DTC P0031 00: HO2S Heater Control Circuit Low
Voltage Sensor 1 |
| DTC P0032 00: HO2S Heater Control Circuit High
Voltage Sensor 1 |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Ignition Voltage
|
P0030 00
|
P0030 00
|
—
|
P0131 5A, P0131 12
|
HO2S Heater Control Sensor 1
|
P0031 00
|
P0030 00
|
P0032 00
|
—
|
|
| |
Circuit/System Description
The heated oxygen sensor (HO2S) heater reduces the time required
for the oxygen sensor to reach operating temperature and maintains
the operating temperature during extended idle periods. When the
ignition is turned to the ON position, ignition voltage is supplied
directly to the sensor heater. The engine control module (ECM)
controls the heater operation by first modulating the control
circuit to ground when the sensors are cold. This prevents the
possibility of thermal shock to the sensor, from condensation
build-up on the sensor, by controlling the sensors rate of heating.
After a predetermined amount of time, the ECM commands the heaters
ON continuously. Once the sensor reaches operating temperature, the
ECM may modulate the heater control circuit to ground, to maintain
a desired temperature.
The ECM controls the heater by grounding the control circuit
with a solid state device called a driver. The driver is equipped
with a feedback circuit that is pulled-up to voltage. The ECM can
determine if the control circuit is open, shorted to ground, or
shorted to a voltage by monitoring the feedback voltage.
Conditions for Running the DTC
| • |
The ignition voltage is
between 10–18 V. |
| • |
The engine speed is greater
than 80 RPM. |
| • |
The HO2S heater is commanded
ON and OFF at least once during the ignition cycle. |
| • |
The DTCs run continuously once
the above conditions are met for 1 s. |
Conditions for Setting the DTC
P0030
The ECM detects an open in the heater circuits of the HO2S when the
heater is commanded ON.
P0031
The ECM detects a short to ground in the heater circuits of the
HO2S when the heater is commanded ON.
P0032
The ECM detects a short to voltage in the heater circuits of the
HO2S when the heater is commanded ON.
Action Taken When the DTC Sets
DTC P0030, P0031 and P0032 are Type B DTCs.
Conditions for Clearing the DTC
DTC P0030, P0031 and P0032 are Type B DTCs.
Diagnostic Aids
| • |
If the condition is
intermittent, move the harnesses and connectors, with the engine
operating, while monitoring the scan tool Circuit Status parameters
for the component. The Circuit Status parameters change from OK or
Not Run to Fault if there is a condition with the circuit or a
connection. |
| • |
An open fuse in the HO2S
heater circuit may be caused by the heater element. The condition
may not be present until the sensor operates for a period of time.
If no fault is present in the heater circuit, monitor the amperage
of the heater using the DMM to determine if the heater element is
the cause of the open fuse. Inspect the sensor pigtail or the
harness for contacting the exhaust system. |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
| 1. |
Engine idling at operating
temperature for at least 30 s. Observe the DTC information, DTCs
P0030, P0031 or P0032 should not set. |
| 2. |
Operate the vehicle within the
Conditions for Running the DTC to verify the DTC does not reset.
You may also operate the vehicle within the conditions that you
observed from the Freeze Frame/Failure Records data. |
Circuit/System Testing
| 1. |
Ignition OFF, disconnect the
harness connector at the B52 Heated Oxygen Sensor. |
|
Note: The ignition
circuit supplies voltage to other components. Make sure you test
all circuits for a short to ground or test all components for being
shorted that share the ignition circuit.
|
| 2. |
Ignition ON, verify that a
test lamp illuminates between the ignition circuit terminal 4 and
ground. |
| ⇒ |
If the test lamp does not illuminate, test the
ignition circuit for a short to ground or an open/high resistance.
If the circuit tests normal and the ignition circuit fuse is open,
test all the components connected to the ignition circuit and
replace as necessary. |
| 3. |
Connect a test lamp between
the heater control circuit terminal 3 and B+. The test lamp should
not illuminate. |
| ⇒ |
If the test lamp is always ON, test the control
circuit for a short to ground. If the circuit test normal, replace
the K20 Engine Control Module. |
|
Note: The control
circuit for the HO2S heater is pulled-up to voltage within the ECM,
3.0–4.0 V on the control circuit is normal.
|
| 4. |
Idle the engine, and verify
the test lamp illuminates or flashes. |
| ⇒ |
If the test lamp is always OFF, test the control
circuit for an open/high resistance. If the circuit/connections
test normal, replace the K20 Engine Control Module. |
| 5. |
Ignition ON, test for
3.0–4.0 V between the control circuit terminal 3 and
ground. |
| ⇒ |
If not within the specified range, test the
control circuit for a short to voltage. If the circuit/connections
test normal, replace the K20 Engine Control Module. |
| 6. |
If all circuits/connections
test normal, test or replace the B52 Heated Oxygen Sensor.
|
Component Testing
Static Test
| 1. |
Ignition OFF, disconnect the
harness connector at the B52 Heated Oxygen Sensor. |
| 2. |
Test the B52 Heated Oxygen
Sensor resistance for 5–25 Ω. |
| ⇒ |
If not within the specified range, replace the B52
Heated Oxygen Sensor. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
