DTC P1134 or P1154 w/ Delphi HO2S
Circuit Description
This diagnostic applies only to vehicles built with Delphi heated oxygen
sensors. To identify the heated oxygen sensor refer to
Oxygen Sensor Identification (4.8L/5.3L/6.0L)
The powertrain control module (PCM) monitors the heated oxygen sensor (HO2S) activity. During the monitor period the PCM counts the number of times that the HO2S responds from rich to lean and from lean to rich and adds the amount of time it took to complete all transitions. With this information, an average time for all transitions can be determined. The PCM then divides the rich to lean average by the lean to rich average to obtain a ratio. A DTC P1134 sets if the HO2S ratio is not within range.
Conditions for Running the DTC
| • | DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0200, P0300, P0401, P0404, P0405, P0410, P0440, P0442, P0446, P0452, P0453, P1120, P1125, P1220, P1221, P1258, P1404, P1415, P1416, P1514, P1515, P1516, P1517, or P1518 are not set. |
| • | The engine coolant temperature (ECT) is more than 65°C (149°F). |
| • | The engine run time is more than 160 seconds. |
| • | The EVAP purge solenoid command is more than 0 percent. |
| • | The mass air flow (MAF) is between 23-50 g/s. |
| • | The engine speed is between 1,200-3,000 RPM. |
| • | Vehicles without throttle-actuated control (TAC), the throttle position (TP) is more than 5 percent. |
| • | Vehicles with throttle-actuated control (TAC), the throttle position (TP) indicated angle is 5 percent more than the value observed at idle. |
| • | The loop status is closed. |
| • | The ignition 1 signal is between 9-18 volts. |
| • | The fuel tank level remaining is more than 10 percent. |
| • | Intrusive tests are not in progress. |
| • | The scan tool output controls are not active. |
Conditions for Setting the DTC
The HO2S transition time ratio is not within a calibrated range for 100 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
Important: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.
| • | Using the Freeze Frame/Failure Records data may aid in locating an intermittent condition. If the DTC cannot be duplicated, the information included in the Freeze Frame/Failure Records data can be useful in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also be used to determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed. |
| • | An oxygen supply inside the HO2S is necessary for proper operation. This supply of oxygen is provided through the HO2S wires. All HO2S wires and connections should be inspected for breaks or contamination. Refer to Heated Oxygen Sensor Wiring Repairs in Wiring Systems. |
For an intermittent, refer to Intermittent Conditions .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step determines if the fault is present. This test may take 5 minutes for the diagnostic to run. For any test that requires probing the PCM or a component harness connector, use the connector test adapter kit . Using this kit prevents damage to the harness connector terminals.
-
When DTCs P1134 and P1154 are set at the same time, this is a good indication that a fuel contamination condition is present.
-
An exhaust leak 15.2-30.5 cm (6-12 in) away from the HO2S can cause a DTC to set.
-
This step tests the HO2S for being tight and the connectors and circuits are OK.
-
This step tests the integrity of the HO2S low signal circuit to the PCM.
-
This step tests the integrity of the signal circuits to the PCM.
Step | Action | Values | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Important: This diagnostic applies only to vehicles built with Delphi 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 | |||||||||
|
Important: If any DTCs are set, except P1134 or P1154, refer to those DTCs before proceeding with this diagnostic table.
Did DTC P1134 or P1154 fail this ignition? | -- | Go to Step 3 | Go to Diagnostic Aids | |||||||||
Did both DTC P1134 and P1154 fail this ignition? | -- | Go to Step 8 | Go to Step 4 | |||||||||
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 5 | |||||||||
Visually and physically inspect the following items:
Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 6 | |||||||||
Does the scan tool indicate a voltage within the specified range? | 350-550 mV | Go to Step 7 | Go to Step 10 | |||||||||
Does the scan tool indicate a voltage below the specified value? | 200 mV | Go to Step 13 | Go to Step 9 | |||||||||
8 |
Important: Determine and correct the cause of the contamination before replacing
a sensor. Inspect for the following conditions:
Replace the affected heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 , or refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 . Did you complete the replacement? | -- | Go to Step 14 | -- | ||||||||
9 |
Does the DMM indicate a voltage near the specified value? | 5 V | Go to Step 12 | Go to Step 11 | ||||||||
10 | Repair the high signal circuit for a short to ground or a short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 14 | -- | ||||||||
11 | Repair the open HO2S low system circuits, or repair the faulty PCM connections. Refer to Wiring Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 14 | -- | ||||||||
12 | Repair the HO2S high signal circuit for an open, or repair the faulty PCM connections. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 14 | -- | ||||||||
13 | Replace the affected HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 , or refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 . Did you complete the replacement? | -- | Go to Step 14 | -- | ||||||||
14 |
Does the DTC run and pass? | -- | Go to Step 15 | Go to Step 2 | ||||||||
15 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |||||||||
DTC P1134 or P1154 w/ Denso HO2S
Circuit Description
This diagnostic applies only to vehicles built with Denso heated oxygen
sensors. To identify the heated oxygen sensor refer to
Oxygen Sensor Identification (4.8L/5.3L/6.0L)
The PCM monitors the heated oxygen sensor (HO2S) activity. During the monitor period the PCM counts the number of times that the HO2S responds from rich to lean and from lean to rich and adds the amount of time it took to complete all transitions. With this information, an average time for all transitions can be determined. The PCM then divides the rich to lean average by the lean to rich average to obtain a ratio. A DTC P1134 sets if the HO2S ratio is not within range.
Conditions for Running the DTC
| • | DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0200, P0300, P0401, P0404, P0405, P0410, P0440, P0442, P0446, P0452, P0453, P1120, P1125, P1220, P1221, P1258, P1404, P1415, P1416, P1514, P1515, P1516, P1517, or P1518 are not set. |
| • | The engine coolant temperature (ECT) is more than 65°C (149°F). |
| • | The engine run time is more than 160 seconds. |
| • | The EVAP purge solenoid command is more than 0 percent. |
| • | The mass air flow (MAF) is between 23-50 g/s. |
| • | The engine speed is between 1,200-3,000 RPM. |
| • | Vehicles without throttle-actuated control (TAC), the throttle position (TP) is more than 5 percent. |
| • | Vehicles with throttle-actuated control (TAC), the throttle position (TP) indicated angle is 5 percent more than the value observed at idle. |
| • | The loop status is closed. |
| • | The ignition 1 signal is between 9-18 volts. |
| • | The fuel tank level remaining is more than 10 percent. |
| • | Intrusive tests are not in progress. |
| • | The scan tool output controls are not active. |
Conditions for Setting the DTC
The HO2S transition time ratio is not within a calibrated range for 100 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
Important: Never solder the HO2S wires. For proper wire and connector repairs, refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Check for the following conditions:
| • | An improperly installed air cleaner outlet duct |
| • | The air cleaner outlet duct for a collapsed duct, restrictions, or a missing or plugged air filter |
| • | Throttle body and intake manifold vacuum leaks |
| • | A damaged or blocked throttle body inlet |
| • | Exhaust system for corrosion, leaks, or loose or missing hardware. Refer to Exhaust Leakage in Engine Exhaust |
| • | The HO2S is installed securely and the pigtail harness is not contacting the exhaust manifold or wires |
| • | HO2S contamination |
| • | The vacuum hoses for splits, kinks, and proper connections |
| • | Excessive water, alcohol, or other contaminants in the fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis |
| • | PCM sensor grounds that are clean, tight, and properly positioned |
An intermittent may be caused by any of the following conditions:
| • | A poor connection |
| • | Rubbed through wire insulation |
| • | A broken wire inside the insulation |
Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
HO2S contamination is indicated if multiple Response, Switching or Time Ratio HO2S DTCs are set.
-
An HO2S contaminated by silicon will have a white, powdery deposit on the portion of the HO2S that is exposed to the exhaust stream. The usual cause of silica contamination is the use of unapproved silicon room temperature vulcanizing (RTV) engine gasket material or the use of silicon based sprays or fluids within the engine.
If the cause of this contamination is not corrected, the replacement HO2S will also get contaminated.
-
Even small exhaust leaks can cause slow response from the HO2S.
-
An HO2S contaminated by silicon will have a white, powdery deposit on the portion of the HO2S that is exposed to the exhaust stream. The usual cause of silica contamination is the use of unapproved silicon RTV engine gasket material or the use of silicon based sprays or fluids within the engine. If the cause of this contamination is not corrected, the replacement HO2S will also get contaminated.
-
If the voltage observed in step 8 is less than the range specified, a short between the HIGH signal and the LOW reference circuits, or a short between the HIGH signal circuit and ground is indicated. With the HO2S and the PCM disconnected, the resistance between the HIGH signal and the LOW reference circuits, and the resistance between the HIGH signal circuit and ground should measure infinite.
If the voltage observed in step 8 is more than the range specified, a short between the HIGH signal circuit and an ignition voltage source is indicated.
-
If the voltage observed in step 9 is not below the voltage specified, a high resistance, or open, HIGH signal or a LOW reference circuit is indicated.
Good circuit continuity measures less than 5 ohms with the PCM and sensor disconnected. Measure between the PCM connector and the HO2S connector. Ensure that the PCM terminal contact is good.
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 | |||||||||||||||||||||||||||||||||
In addition to this DTC, check for the following HO2S DTCs:
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 Step 5 | |||||||||||||||||||||||||||||||||
Did you find and correct the condition? | -- | Go to Step 18 | -- | |||||||||||||||||||||||||||||||||
5 |
Did this DTC 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:
Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition? | -- | Go to Step 18 | Go to Diagnostic Aids | ||||||||||||||||||||||||||||||||
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 8 | |||||||||||||||||||||||||||||||||
8 |
Is the HO2S voltage within the value range specified? | 351-551 mV | Go to Step 9 | Go to Step 13 | ||||||||||||||||||||||||||||||||
9 |
Is the HO2S voltage less than the value specified? | 20 mV | Go to Step 10 | Go to Step 14 | ||||||||||||||||||||||||||||||||
10 |
Does the test lamp illuminate? | -- | Go to Step 11 | Go to Step 15 | ||||||||||||||||||||||||||||||||
11 | Connect the test lamp between the HO2S heater ignition voltage circuit terminal and the HO2S heater ground circuit terminal, both on engine harness side. Does the test lamp illuminate? | -- | Go to Step 12 | Go to Step 16 | ||||||||||||||||||||||||||||||||
Did you find and correct the condition? | -- | Go to Step 17 | -- | |||||||||||||||||||||||||||||||||
Did you complete the repair? | -- | Go to Step 18 | Go to Diagnostic Aids | |||||||||||||||||||||||||||||||||
Did you complete the repair? | -- | Go to Step 18 | -- | |||||||||||||||||||||||||||||||||
15 | Repair the HO2S heater ignition voltage circuit. 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 affected HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 , or refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 . Did you complete the replacement? | -- | Go to Step 18 | -- | ||||||||||||||||||||||||||||||||
18 |
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? | -- | System OK | |||||||||||||||||||||||||||||||||
