Step
| Action
| Values
| Yes
| No
|
Schematic Reference:
Engine Controls Schematics
Important: This diagnostic applies only to vehicles built with Denso heated oxygen
sensors. To identify the heated oxygen sensor, refer to
|
1
| Did
you perform the Diagnostic System Check-Engine Controls?
| --
| Go to
Step 2
| Go to
Diagnostic System Check - Engine Controls
|
2
| In addition to this DTC, check for the following HO2S DTCs:
• | The opposite bank sensor slow response DTC |
• | Either bank sensor insufficient switching DTC |
• | Either bank sensor transition time ratio DTC |
Are any of the above listed HO2S DTCs set?
| --
| Go to
Step 4
| Go to
Step 3
|
3
| Are any powertrain component DTCs set?
| --
| Go to
Diagnostic Trouble Code (DTC) List
| Go to
Step 5
|
4
|
- The HO2S sensors have been contaminated. Replace the affected
HO2S sensors. Refer to
Heated Oxygen Sensor Replacement - Bank 1 Sensor 1
and to
Heated Oxygen Sensor Replacement - Bank 1 Sensor 2
.
- The contamination source must be removed prior to operating the
engine with the replacement sensors. Possible sources include the following
:
• | The use of incorrect silicon RTV sealant |
• | An engine coolant leak into the combustion chamber |
• | An excessive engine oil consumption |
• | The use of silicon contaminated fuel |
• | The use of fuel containing lead |
Has the contamination source been removed and the affected sensors replaced?
| --
| Go to
Step 18
| --
|
5
|
- Use the scan tool in order to store the DTC information from the
PCM into the scan tool.
- Clear the DTC Information from the PCM.
- Reset the fuel trim values.
- Start and idle the engine until a normal operating temperature
is reached.
- Operate the engine within the Conditions for Running the DTC.
Did this diagnostic test run and fail this ignition?
| --
| Go to
Step 7
| Go to
Step 6
|
6
|
- The condition that set this DTC is not present. This DTC may have
been set by one of the following conditions:
• | An exhaust system leak between the engine and the HO2S. Refer
to
Exhaust Leakage
in Engine Exhaust |
• | Poor HO2S connector terminal contact |
• | Any water intrusion into the HO2S connector |
• | An improperly torqued HO2S |
• | An HO2S with an inoperative heater |
• | Poor PCM connector terminal contact |
• | An HO2S high or low reference circuit with one of the following
conditions: |
- | An excessive circuit resistance of more than 5 ohms |
• | A contaminated HO2S. Contamination can include the following: |
- | The use of incorrect RTV sealant |
- | An excessive engine oil or coolant consumption |
- Repair any engine conditions as necessary.
Did you find and correct the condition?
| --
| Go to
Step 18
| Go to
Diagnostic Aids
|
7
|
- Check the exhaust system for leaks between the HO2S and the engine.
Refer to
Exhaust Leakage
in Engine
Exhaust
- Repair the exhaust as necessary.
- Check the HO2S and PCM connectors for proper terminal contact.
- Repair the terminal contact as necessary. Refer to
Connector Repairs
in Wiring Systems.
Did you find and correct the condition?
| --
| Go to
Step 18
| Go to
Step 8
|
8
|
- Turn OFF the ignition.
- Disconnect the HO2S connector for the sensor that applies to this
DTC.
- Jumper the HO2S low reference circuit terminal to a known good
ground.
- Turn ON the ignition, leaving the engine OFF.
- Use the scan tool in order to monitor the HO2S voltage for the
sensor that applies to this DTC.
Is the HO2S voltage within the specified range?
| 351-551 mV
| Go to
Step 9
| Go to
Step 13
|
9
|
- Jumper the HO2S high signal circuit to ground.
- Use the scan tool in order to monitor the HO2S voltage for the
sensor that applies to this DTC.
Is the HO2S voltage less than the specified value?
| 20 mV
| Go to
Step 10
| Go to
Step 14
|
10
|
- Remove the jumper from the HO2S low reference circuit.
- Connect a test lamp between the ignition 1 voltage circuit
terminal of the HO2S heater and a known good ground. Do not use the HO2S
heater ground circuit terminal.
Does the test lamp illuminate?
| --
| Go to
Step 11
| Go to
Step 15
|
11
| Connect the test lamp between the ignition 1 voltage circuit
terminal of the HO2S heater and the ground circuit terminal of the HO2S
heater.
Does the test lamp illuminate
| --
| Go to
Step 12
| Go to
Step 16
|
12
|
- Check for the following contamination sources which may have caused
the HO2S to fail:
• | The use of an incorrect RTV engine sealant |
• | An excessive engine oil or coolant consumption |
- Repair or remove the source of the contamination.
Did you complete the repair?
| --
| Go to
Step 17
| --
|
13
| Repair the short between
the HO2S high signal and the low reference circuits, or repair the short
between the HO2S high signal circuit and an ignition voltage source.
Refer to
Wiring Repairs
in Wiring
Systems.
Did you complete the repair?
| --
| Go to
Step 18
| --
|
14
|
- Test the HO2S high signal circuit and the HO2S low reference circuits
for an open or a high circuit resistance.
- Repair the HO2S circuits as necessary. Refer to
Wiring Repairs
in Wiring Systems.
Did you complete the repair?
| --
| Go to
Step 18
| --
|
15
| Repair the ignition positive voltage circuit of the HO2S heater. Refer
to
Wiring Repairs
in Wiring Systems.
Did you complete the repair?
| --
| Go to
Step 18
| --
|
16
| Repair the HO2S heater ground circuit. Refer to
Wiring Repairs
in Wiring Systems.
Did you complete the repair?
| --
| Go to
Step 18
| --
|
17
| Replace the HO2S. Refer to
Heated Oxygen Sensor Replacement - Bank 1 Sensor 1
or to
Heated Oxygen Sensor Replacement - Bank 1 Sensor 2
.
Did you complete the repair?
| --
| Go to
Step 18
| --
|
18
|
- Use the scan tool in order to clear the DTCs.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the DTC
as specified in the supporting text.
Does the DTC run and pass?
| --
| Go to
Step 19
| Go to
Step 2
|
19
| With a scan tool, observe the stored information, Capture Info.
Does the scan tool display any DTCs that you have not diagnosed?
| --
| Go to
Diagnostic Trouble Code (DTC) List
| System OK
|