Diagnostic Starting Point - Engine Cooling
Begin the system diagnosis with the diagnostic system check. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information. The Diagnostic System Check - Vehicle will provide the following information
- The identification of the control modules which command the system
- The ability of the control modules to communicate through the serial data circuits
- The identification of any stored DTCs and their status
The use of the Diagnostic System Check - Vehicle will identify the correct procedure for diagnosing the system and where the procedure is located.
Scan Tool Output Controls
| Scan Tool Output Control | Additional Menu Selection(s) | Description |
|---|---|---|
| Fan Relay | Engine Output Controls | The scan tool displays a Commanded State of None, Off or On. This allows you to communicate with the ECM and activate or deactivate the cooling fan relay, manually turning the fans On and Off. |
Engine Control Module (ECM) Scan Tool Output Controls 2.2L (L61) only
Scan Tool Data List
| Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
|---|---|---|---|
| Ignition Switch in RUN/Engine running/Automatic Transmission in PARK/Air Conditioner is OFF | |||
| ECT | HVAC Data | °C/°F | Varies |
| FC Relay 1 Command | HVAC Data | ON/OFF | OFF |
| Low Coolant Level | HVAC Data | YES/NO | NO |
Engine Control Module (ECM) 2.2L (L61)
| Scan Tool Parameter | Data List | Units Displayed | Typical Data Value |
|---|---|---|---|
| Ignition Switch in RUN/Engine running/Automatic Transmission in PARK/Air Conditioner is OFF | |||
| ECT | HVAC Data | °C/°F | Varies |
| FC Relay 1 Command | HVAC Data | ON/OFF | OFF |
| FC Relay 2 Command | HVAC Data | ON/OFF | OFF |
Powertrain Control Module (PCM) 2.0L (LSJ)
Circuit Description
The coolant temperature telltale on the instrument panel cluster (IPC) has the ability to illuminate as a result of an engine over temperature condition. The engine control module (ECM) will send a message to the IPC over the class 2 link to turn the coolant temperature telltale ON if the engine coolant temperature (ECT) exceeds the temperature calibration value listed under Conditions for Setting the DTC.
DTC Descriptors
This diagnostic procedure supports the following DTC
P0217 Engine Coolant Overtemperature
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
- The ECT is greater than 118°C (244°F).
- No other ECT sensor DTCs have been set.
- The ECM will command the A/C relay OFF if the temperature of the engine coolant is greater than 118°C (244°F).
DTC P0217 diagnostic runs continuously once the above conditions have been met.
Conditions for Clearing the MIL/DTC
- The ECM will turn the malfunction indicator lamp (MIL) OFF after 3 consecutive trips that the diagnostic has been run and passed.
- The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
- The DTC can be cleared by using the scan tool.
Diagnostic Aids
- Cooling fan inoperative - Refer to «Cooling Fan Inoperative (2.2L (L61))»(ref-196980-S09814539102005101000000) or «Cooling Fan Inoperative (2.0L (LSJ))»(ref-196980-S14676388782005101000000) .
- Engine cooling system overheated condition (thermostat, low engine coolant etc.) - Refer to «Engine Overheating»(ref-196980-S32432214472005101000000) .
- Radiator or condenser air flow restricted
- Air dam missing or loose
- Overload due to trailer towing
- ECT sensor leaking engine coolant into ECT sensor harness connector causing elevated temperatures
- ECT sensor skewed
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Engine Cooling Schematics (2.2L) or Engine Cooling Schematics (2.0L) Connector End View Reference: Cooling System Connector End Views | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Check the engine cooling fans for proper operation. Are the engine cooling fans operative? | Go to Engine Overheating | Go to Symptoms - Engine Cooling |
DTC P0217
Battery positive voltage is supplied to the cooling fan relay through the 30 A cooling fan fuse located in the underhood fuse block. The engine control module (ECM) controls the cooling fan relay by grounding the cooling fan relay control circuit through an internal solid state device called a driver. The primary function of the driver is to supply the ground for the component being controlled. Each driver has a fault line which is monitored by the ECM. When the ECM is commanding a component ON, the voltage potential of the control circuit should be low, near 0 volts. When the ECM is commanding the control circuit to a component OFF, the voltage potential of the circuit should be high, near battery voltage. If the fault detection circuit senses a voltage other than what is expected, the DTC will set.
The ECM will monitor the control circuit for the following conditions
- A short to ground
- A short to voltage
- An open circuit
- An open relay coil
- An internally shorted or excessively low resistance relay coil.
When the ECM detects any of the above conditions, the DTC will set and the affected driver will be disabled.
This diagnostic procedure supports the following DTCs
- P0480 is for the low speed cooling fan relay control circuit.
- P0481 is for the high speed cooling fan relay control circuit.
- P0691 Is for the cooling fan relay control circuit.
- The ignition is ON.
- The battery voltage is more than 9 volts.
- The ECM detects an open, a short to ground, or a short to voltage on the cooling fan relay control circuit.
- The condition must be present for a minimum of 6 seconds.
Action Taken When the DTC Sets
- The ECM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
- The ECM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data.
- The ECM will turn OFF the MIL during the third consecutive trip in which the diagnostic has been run and passed.
- The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
- The DTC can be cleared by using the scan tool.
- If the condition is not present, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-196941-S32978396082005101000000) in Wiring Systems.
- Review the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.
The powertrain control module (PCM) controls the low speed cooling fan operation by grounding the cool fan 1 relay control circuit with an internal solid state device called a driver. For high speed cooling fan operation, the PCM grounds the cool fan 2 and S/P relay control circuit at the same time the cool fan 1 control circuit is grounded. Battery positive voltage is supplied to the cool fan 1, cool fan 2 and S/P fan relays. When the PCM is commanding a fan relay ON, the voltage of the control circuit should be low, near 0 volts. When the PCM is commanding a fan relay OFF, the voltage potential of the control circuit should be high, near battery voltage. If the fault detection circuit senses a voltage other than what is expected, the DTC will set.
If the PCM detects an improper voltage level on the cool fan 1 or cool fan 2 speed driver circuits, then code P0480, P0481 or P0691 will set and the effected driver will be disabled.
This diagnostic procedure supports the following DTCs
- P0480 is for the low speed cooling fan relay control circuit.
- P0481 is for the high speed cooling fan relay control circuit.
- P0691 Is for the cooling fan relay control circuit.
- The ignition is ON.
- System voltage is between 9-18 volts.
- The relay control circuit is transitioned from OFF to ON or ON to OFF.
- The PCM detects an open, a short to ground, or a short to voltage on the cooling fan relay control circuit.
- The above conditions are present for at least 30 seconds.
- The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
- The PCM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data.
- The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic has been run and passed.
- The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
- The DTC can be cleared by using the scan tool.
- If the condition is not present, refer to «Testing for Intermittent Conditions and Poor Connections»(ref-196941-S32978396082005101000000) in Wiring Systems.
- Review the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.
Visual/Physical Inspection
- Inspect for aftermarket devices which could affect the operation of the Cooling System. Refer to «Checking Aftermarket Accessories»(ref-196941-S26961180052005101000000) in Wiring Systems.
- Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
- Inspect the surge tank reservoir for the proper coolant level.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom
- «Low Engine Coolant Indicator Always On»(ref-196980-S35978889602005101000000)
- «Cooling Fan Always On (2.2L (L61))»(ref-196980-S17639624692005101000000) or «Cooling Fan Always On (2.0L (LSJ))»(ref-196980-S42569634142005101000000)
- «Cooling Fan Inoperative (2.2L (L61))»(ref-196980-S09814539102005101000000) or «Cooling Fan Inoperative (2.0L (LSJ))»(ref-196980-S14676388782005101000000)
- «Engine Overheating»(ref-196980-S32432214472005101000000)
- «Loss of Coolant»(ref-196980-S30807045782005101000000)
- «Thermostat Diagnosis»(ref-196980-S29946057012005101000000)
- «Coolant Heater Inoperative»(ref-196980-S16974138172005101000000)
- «Engine Fails To Reach Normal Operating Temperature»(ref-196980-S04419814632005101000000)
Thermostat Diagnosis
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Pressure test the cooling system and the cap for leaks. Repair any leaks before proceeding. These engines use a 82°C (180°F) thermostat. The ambient temperatures should be within the specified range given. Set the HVAC controls in the OFF position. Run the cold engine at idle (68-70°F) for 15-20 minutes before checking the engine temperature. Check the engine coolant temperature at idle with the Scan Tool . Is the engine coolant temperature (ECT) between 85-96°C (185-205°F)? | 13-38°C (55-100°F) | System OK | Go to Step 2 |
| 2 | Is the ECT below 85°C (185°F)? | Go to Step 3 | Go to Step 4 | |
| 3 | The thermostat is opening early, or the thermostat seal is leaking. Replace the thermostat and the thermostat seal. Refer to Thermostat Replacement . Is the repair complete? | System OK | ||
| 4 | Is the ECT over 96°C (205°F)? | Go to Step 5 | ||
| 5 | Is the radiator inlet hot? | Go to Step 6 | Go to Step 7 | |
| 6 | Turn ON the heater. Check if hot air is coming from the heater outlets. Is the air hot? | Go to Step 11 | Go to Step 12 | |
| 7 | There may be air in the system. Add coolant to the surge tank if the coolant level is low. Refer to Draining and Filling Cooling System (2.2L (L61)) or Draining and Filling Cooling System (2.0L (LSJ)) . Recheck the radiator inlet hose. Is the inlet hose hot? | Go to Step 6 | Go to Step 8 | |
| 8 | Inspect for blockage in the following areas: The cylinder head The radiator The radiator hoses Is there a blockage? | Go to Step 9 | Go to Step 10 | |
| 9 | Repair the blockage. Recheck the coolant temperature with the Scan Tool . Is the repair complete? | System OK | ||
| 10 | Replace the thermostat. Refer to Thermostat Replacement . Recheck the coolant temperature with the Scan Tool . Is the repair complete? | System OK | ||
| 11 | Inspect for blockage in the radiator. Is there any blockage? | Go to Step 9 | Go to Step 10 | |
| 12 | Accelerate the engine several times in order to remove any air from the system. Inspect for blockage in the heater circuit. Inspect for any pinched or buckled hoses. Is there any blockage? | Go to Step 9 | Go to Step 13 | |
| 13 | Refer to Diagnostic Starting Point - Heating, Ventilation and Air Conditioning in Heating, Ventilation and Air Conditioning. Is the repair complete? | System OK |
Thermostat Diagnosis
Pressure Cap Testing
Tools Required
- SA9141E Cooling System Pressure Tester. See «Special Tools»(ref-196980-S01424700812005101000000) .
- J 42401 Radiator Cap/Surge Tank Test Adapter. See «Special Tools»(ref-196980-S01424700812005101000000) .
- J 46143 Intercooler Reservoir Cap Test Adapter
- Remove the pressure cap.
- Wash the pressure cap sealing surface with water.
- Use SA9141E (1) with one of the following attachments (2). See «Special Tools»(ref-196980-S01424700812005101000000) . J 42401 in order to test the radiator cap. See «Special Tools»(ref-196980-S01424700812005101000000) . J 46143 in order to test the intercooler reservoir cap
- Test the pressure cap for the following conditions: Pressure the release when SA9141E exceeds the pressure rating of the pressure cap. See «Special Tools»(ref-196980-S01424700812005101000000) . Maintain the rated pressure for at least 10 seconds. Note the rate of pressure loss.
- Replace the pressure cap under the following conditions: The pressure cap does not release the pressure which exceeds the rated pressure of the cap. The pressure cap does not hold the rated pressure.
Cooling System Leak Testing (2.2L (L61))
Tools Required
- SA9141E Cooling System Pressure Tester. See «Special Tools»(ref-196980-S01424700812005101000000) .
- J 42401 Radiator Cap/Surge Tank Test Adapter. See «Special Tools»(ref-196980-S01424700812005101000000) .
Cooling System Leak Testing
- Remove the pressure cap.
- Test the operation of the pressure cap. Refer to «Pressure Cap Testing»(ref-196980-S36040133352005101000000) .
- Wash the pressure cap mating surface with water.
- Use the SA9141E with J 42401 in order to apply pressure to the cooling system. See «Special Tools»(ref-196980-S01424700812005101000000) . Do not exceed the pressure cap rating.
- The cooling system should hold the rated pressure for at least 2 minutes. Observe the gage for any pressure loss.
- Repair any leaks as required.
Cooling System Leak Testing (2.0L (LSJ))
Tools Required
- SA9141E Cooling System Pressure Tester. See «Special Tools»(ref-196980-S01424700812005101000000) .
- J 42401 Radiator Cap/Surge Tank Test Adapter. See «Special Tools»(ref-196980-S01424700812005101000000) .
- J 46143 Intercooler Reservoir Cap Test Adapter
- Remove the pressure cap.
- Test the operation of the pressure cap. Refer to «Pressure Cap Testing»(ref-196980-S36040133352005101000000) .
- Wash the pressure cap mating surface with water.
- Use SA9141E with one of the following attachments to apply pressure to the cooling system. See «Special Tools»(ref-196980-S01424700812005101000000) . J 42401 in order to test the radiator cap. See «Special Tools»(ref-196980-S01424700812005101000000) . J 46143 in order to test the intercooler reservoir cap
- The cooling system should hold the rated pressure for at least 2 minutes. Observe the gage for any pressure loss.
- Repair any leaks as required.