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Heated Oxygen Sensor Circuit – Failed In-Range High
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Overview
| CODE | REASON | EFFECT |
| Fault Code: 2219 PID: S65 SPN: 724 FMI: 0/16 LAMP: Amber SRT: |
Heated Oxygen Sensor Circuit – Failed In-Range High The measured air-to-fuel ratio is greater than the desired calculated air-to-fuel ratio. |
Possible reduced performance. No closed loop operation. |
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Heated Oxygen Sensor Circuit |
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Circuit Description
The electronic service tool (ECM) uses this sensor to determine the composition of the exhaust gas and then, to adjust fueling.
Component Location
The heated oxygen sensor is located in the exhaust outlet connection, after the turbocharger.
Shop Talk
The heated oxygen sensor measures the partial pressure of oxygen present in the exhaust gas. It measures this oxygen presence in lambda (L). The air-to-fuel ratio (stoichiometric) is 1L :16.5. The approximate lean-burn condition for the engine is 1.4.
The ECM will read an in-range high fault if the engine is running lean or the heated oxygen sensor or heated oxygen sensor circuit has failed. An exhaust leak can cause this fault by not providing enough back pressure to the heated oxygen sensor. Also, If there are any intake leaks after the throttle actuator the engine can also run lean due to low fuel pressure problems which can cause this fault to activate. If this troubleshooting tree does not fix the problem, the ECM can be the fault.
Cautions and Warnings
WARNING ![]() Do not touch the heated oxygen sensor until it has cooled. The heated oxygen sensor operates at high temperature and can cause personal injury.
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CAUTION ![]() Do not use any lubricant in the heated oxygen sensor connector. The sensor will not perform correctly with any grease in the connector. |
CAUTION ![]() To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM. |
CAUTION ![]() To reduce the possibility of pin and harness damage, use the following test lead when taking a measurement: |
Troubleshooting Steps
| STEPS | SPECIFICATIONS | |
|---|---|---|
| STEP 1. | Check the fault codes. | |
| STEP 1A. Check for fault codes. | Fault Code 752 active? | |
| STEP 1B. Check for an inactive fault code. | Fault Code 2219 inactive? | |
| STEP 2. | Check the engine harness and heated oxygen sensor. | |
| STEP 2A. Inspect the engine harness and heated oxygen sensor connector pins. | Dirty or damaged pins? | |
| STEP 2B. Check for an open circuit in the engine harness. | Less than 10 ohms? | |
| STEP 2C. Check for a pin to pin short circuit in the engine harness. | Greater than 100k ohms? | |
| STEP 2D. Check for an inactive fault code. | Fault Code 2219 inactive? | |
| STEP 3. | Check the fuel pressure. | |
| STEP 3A. Verify secondary fuel pressure. | Is pressure correct for the engine family? | |
| STEP 3B. Check for a stuck open fuel control valve. | Secondary fuel pressure drop within 50 seconds of key on? | |
| STEP 3C. Gas mass flow compensation is correct. | Is the gas flow compensation a positive 25 or higher? | |
| STEP 4. | Check the intake and exhaust system | |
| STEP 4A. Check the intake and exhaust system for air leaks. | Air leaks? | |
| STEP 4B. Check for an inactive fault code. | Fault Code 2219 inactive? | |
| STEP 5. | Clear the fault codes. | |
| STEP 5A. Disable the fault code. | Fault Code 2219 inactive? | |
| STEP 5B. Clear the inactive fault codes. | All fault codes cleared? | |
Guided Step 1 – Check the fault codes.
| Guided Step 1A – Check for fault codes. | |
|---|---|
Conditions
Action
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Fault Code 752 active? |
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| YES | NO |
| No Repair | No Repair |
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Fault Code 752
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| Guided Step 1B – Check for an inactive fault code. | |
|---|---|
Conditions
Action
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Fault Code 2219 inactive? |
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| YES | NO |
| No Repair | No Repair |
Guided Step 2 – Check the engine harness and heated oxygen sensor.
| Guided Step 2A – Inspect the engine harness and heated oxygen sensor connector pins. | |
|---|---|
Conditions
Action
Refer to the circuit diagram or wiring diagram for connector pin identification. For general inspection techniques, refer to Component Connector and Pin Inspection, Procedure 019-361. |
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Dirty or damaged pins? |
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| YES | NO |
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A defective connection has been detected in the ECM, engine harness or heated oxygen sensor connector. Repair the damaged pins. Repair or replace the engine harness, or replace the sensor, whichever has the damaged pins.
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No Repair |
| Guided Step 2B – Check for an open circuit in the engine harness. | |
|---|---|
Conditions
Action
Refer to the circuit diagram or wiring diagram for connector pin identification. For general resistance measurement techniques, refer to Resistance Measurements Using a Multimeter and Wiring Diagram, Procedure 019-360 |
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Less than 10 ohms? |
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| YES | NO |
| No Repair |
An open adjustment current, SIGNAL or RETURN circuit has been detected in the engine harness. Repair the damaged pins. Repair or replace the engine harness, whichever has the damaged pins. |
| Guided Step 2C – Check for a pin to pin short circuit in the engine harness. | |
|---|---|
Conditions
Action
Refer to the circuit diagram or wiring diagram for connector pin identification. For general resistance measurement techniques, refer to Resistance Measurements Using a Multimeter and Wiring Diagram, Procedure 019-360 |
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Greater than 100k ohms? |
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| YES | NO |
| No Repair |
A pin to pin short circuit on the signal line or adjustment current line has been detected in the engine harness. Repair the damaged pins. Repair or replace the engine harness, whichever has the damaged pins. |
| Guided Step 2D – Check for an inactive fault code. | |
|---|---|
Conditions
Action
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Fault Code 2219 inactive? |
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| YES | NO |
| No Repair | No Repair |
Guided Step 3 – Check the fuel pressure.
| Guided Step 3A – Verify secondary fuel pressure. | |
|---|---|
Conditions
Action
B Gas Plus – 60 psia B LPG Plus – 40 psia C and L Gas Plus – 75 psia
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Is pressure correct of the engine family? |
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| YES | NO |
| No Repair |
For more troubleshooting details on low fuel pressure issues, go to Fault Code 2119. |
| Guided Step 3B – Check for a stuck open fuel control valve. | |
|---|---|
Conditions
Action
Note: If the fuel control valve is stuck open, raw fuel will be dumped into the engine and out the exhaust. This will cause the heated oxygen sensor to read a lower than actual air oxygen value. |
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Secondary fuel pressure drop within 50 seconds of key on? |
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| YES | NO |
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A defective fuel control valve has been detected. Replace the fuel control valve. Refer to Procedure 019-102. Use INSITE™ electronic service tool to reset the fuel tables. |
No Repair |
| Guided Step 3C – Gas mas flow compensation is correct. | |
|---|---|
Conditions
Action
Note: Oil contamination of the gas mass flow sensor will cause a low flow reading and over compensate for fuel flow. If the engine is running rich and Fault Code 2219 is active, the gas mass flow sensor must be inspected. Check the fuel filter for excess oil due to improper maintenance. If there is more than one ounce of oil in the fuel filter, than there is a possibility that oil has contaminated the fuel system. The customer must check their gas compression station for oil carry over. |
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Is the gas flow compensation a positive 25 or higher? |
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| YES | NO |
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Replace the gas mass flow sensor. Refer to Procedure 019-101. Use INSITE™ electronic service tool to reset the fuel tables. |
No Repair |
Guided Step 4 – Check for intake and exhaust systems.
| Guided Step 4A – Check the intake and exhaust system for air leaks. | |
|---|---|
Conditions
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Air Leaks? |
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| YES | NO |
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Follow the troubleshooting steps in Procedure 010-024 in the Troubleshooting and Repair Manual C8.3G, C Gas Plus and L Gas Plus Engines, Bulletin 3666206 and Procedure 010-024 in the Troubleshooting and Repair Manual B5.9G, B5.9 LPG, B Gas Plus and B LPG Plus Engines, Bulletin 3666164. |
No Repair |
| Guided Step 4B – Check for an inactive fault code. | |
|---|---|
Conditions
Action
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Fault Code 2219 inactive? |
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| YES | NO |
| No Repair |
Replace the heated oxygen sensor. Refer to Procedure 019-100. Use INSITE™ electronic service tool to reset. |
Guided Step 5 – Clear the fault codes.
| Guided Step 5A – Disable the fault code. | |
|---|---|
Conditions
Action
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Fault Code 2219 inactive? |
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| YES | NO |
| No Repair | No Repair |
| Guided Step 5B – Clear the inactive fault codes. | |
|---|---|
Conditions
Action
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All fault codes cleared? |
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| YES | NO |
| No Repair | No Repair |
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Repair complete
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Appropriate troubleshooting charts
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WARNING
CAUTION