Engine Cooling System: Diagnosis Saturn Aura I

DIAGNOSTIC CODE INDEX

DIAGNOSTIC CODE INDEX

Diagnostic Starting Point - Engine Cooling

Begin the system diagnosis with the diagnostic system check. Refer to Diagnostic System Check - Vehicle . The Diagnostic System Check - Vehicle will provide the following information

1. The identification of the control modules which command the system
2. The ability of the control modules to communicate through the serial data circuits
3. 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.

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(ref-301515-S32423278442008101700000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-301515-S06578354042008101700000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-301515-S28090839972008101700000) provides an overview of each diagnostic category.

Diagnostic Fault Information

Conditions for Running the DTC

1. The ignition is ON.
2. The system voltage is between 9-18 volts.
3. The relay control circuit is transitioned from OFF to ON, or ON to OFF.

Conditions for Setting the DTC

1. An improper voltage level has been detected on the cooling fan relay control circuit.
2. The condition must be present for a minimum of 30 seconds.

Action Taken When the DTC Sets

DTCs P0480 and P0481 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0480 and P0481 are Type B DTCs.

Circuit/System Testing

1. Ignition OFF, disconnect the series/parallel relay, which is cool/fan SER/PAR relay 29.
2. Connect a 30A fused jumper between the normally-open switch contact terminals 30 and 87 at the series/parallel relay connector in order to complete the fan ground circuit. Leave this jumper in place for the remainder of this procedure.
3. Ignition OFF, disconnect the affected relay.
4. Verify that a test lamp does not illuminate between B+ and the affected relay control circuit terminal 85.
5. Remove the test lamp.
6. Command the affected relay ON with a scan tool. Verify the scan tool Relay Control Ckt. Short Volts Test Status Parameter is OK. If not the specified value, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
7. Install a 3A fused jumper wire between the control circuit terminal 85 and B+. Command the affected relay ON with a scan tool. Verify the scan tool Relay Control Ckt Short Volts Test Status Parameter is Fault. If not the specified value, test the control circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
8. Remove the 3A fused jumper wire.
9. Connect a 30A fused jumper between the positive voltage terminal at the battery and the fan voltage supply circuit terminal 87 at the affected relay connector and verify fan activation. If the fan does not activate, test the fan voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the fan.
10. Ignition ON, connect a 30A fused jumper between the relay switch voltage supply circuit terminal 30 and the fan voltage supply circuit terminal 87 at the affected relay connector and verify fan activation. If the fan does not activate, test the affected relay switch voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and its fuse is open, test all connected components and replace as necessary.
11. Ignition ON, verify that a test lamp illuminates between the affected relay coil voltage supply circuit terminal 86 and ground. If the test lamp does not illuminate, test the affected relay coil voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and its fuse is open, test all connected components and replace as necessary.
12. If all circuits and the ECM test normal, replace the affected relay.

1. Perform the «Diagnostic System Check - Vehicle»(ref-301515-S32423278442008101700000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-301515-S06578354042008101700000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-301515-S28090839972008101700000) provide an overview of each diagnostic category.

1. The engine is running.
2. DTC P0116, P0117, P0118, or P0128 are not set.

The coolant temperature is more than 131°C (267.8°F) for more than 7 seconds.

1. DTC P1258 is a Type A DTC.
2. The engine will operate in the Overheated Engine Protection Operating Mode.
3. The IP will illuminate the coolant temperature indicator lamp and the driver information center (DIC), if equipped, may display a message.

DTC P1258 is a Type A DTC.

1. Test the thermostat for correct operation. Refer to «Thermostat Diagnosis»(ref-301507-S02429417092008101700000) .
2. Test the engine cooling system for overheating. Refer to «Engine Overheating»(ref-301507-S06645056062008101700000) .
3. Inspect the water pump and coolant flow for correct operation. Refer to «Water Pump Cleaning and Inspection»(ref-301513-S20416483552008101700000) for the 3.5L engine or «Water Pump Cleaning and Inspection»(ref-301566-S26997368672008101700000) for the 3.6L engine.
4. Inspect the engine mechanical for worn/leaking/cracked cylinder heads or engine block. Refer to «Coolant in Combustion Chamber»(ref-301513-S41866952302008101700000) for the 3.5L engine or «Coolant in Combustion Chamber»(ref-301558-S05193498892008101700000) for the 3.6L engine. Also refer to «Coolant in Engine Oil»(ref-301513-S11678357002008101700000) for the 3.5L engine or «Coolant in Engine Oil»(ref-301558-S32657311652008101700000) for the 3.6L engine.

Important Preliminary Inspections Before Starting

Before using the Symptom diagnosis, perform the following

1. Perform «Diagnostic System Check - Vehicle»(ref-301515-S32423278442008101700000) and verify all of the following items: Ensure that the engine control module (ECM) and indicator lamp are operating correctly. Ensure that there are no diagnostic trouble codes (DTCs) that are stored. Scan tool data is within a normal operating range. Refer to «Control Module References»(ref-301518-S12838675482008101700000) for scan tool information.
2. Verify the customer concern.
3. Perform the Visual/Physical Inspection in this section. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.
4. Locate the correct symptom. Perform the tests and inspections associated with the symptom.

Review the system operation in order to familiarize yourself with the system functions.

Visual/Physical Inspection

Note. Use the connector test adapter kit J 35616-A for any test that requires probing the following items: The PCM harness connectors The electrical center fuse/relay cavities The component terminals The component harness connector Using this kit will prevent damage caused by the improper probing of connector terminals.

Several of the symptom procedures call for a careful visual and physical inspection. This can lead to correcting a condition without further tests and can save time. This inspection should include the following areas

1. Ensure that the control module grounds are clean, tight, and correctly located.
2. Inspect cooling system hoses and pipes for splits, kinks, and proper connections. Inspect thoroughly for any type of a leak or a restriction.
3. Inspect for a dirty or restricted radiator and HVAC condenser.
4. Inspect for aftermarket devices which could affect the operation of the Cooling System.
5. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
6. 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

1. «Cooling Fan Always On»(ref-301507-S29887397962008101700000)
2. «Cooling Fan Inoperative»(ref-301507-S36875022582008101700000)
3. «Engine Overheating»(ref-301507-S06645056062008101700000)
4. «Loss of Coolant»(ref-301507-S26230156032008101700000)
5. «Thermostat Diagnosis»(ref-301507-S02429417092008101700000)
6. «Coolant Heater Inoperative»(ref-301507-S19947298842008101700000)
7. «Engine Fails To Reach Normal Operating Temperature»(ref-301507-S04756939552008101700000)

1. Perform the «Diagnostic System Check - Vehicle»(ref-301515-S32423278442008101700000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-301515-S06578354042008101700000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-301515-S28090839972008101700000) provides an overview of each diagnostic category.

1. Ignition OFF, leave the series/parallel relay in place while disconnecting the other relays.
2. Ignition ON, observe that the fans are not activated. If the fans are not activated, replace the faulty relay. If a fan is activated, test the fan voltage supply circuits for a short to voltage.

1. Perform the «Diagnostic System Check - Vehicle»(ref-301515-S32423278442008101700000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-301515-S06578354042008101700000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-301515-S28090839972008101700000) provides an overview of each diagnostic category.

1. Ignition OFF, disconnect the series/parallel relay, which is cool/fan SER/PAR relay 29.
2. Ignition ON, activate the cooling fan relay 1 with a scan tool. The fan should be OFF. If the fan is activated, test the left fan ground circuit for a short to ground.
3. Ignition OFF, disconnect the remaining relays.
4. Install a 30A fused jumper between the normally-open switch contact terminals 30 and 87 at the series/parallel relay connector in order to complete the fan ground circuit. Leave this jumper in place for the remainder of this procedure.
5. One at a time, connect a 30A fused jumper between the positive terminal at the battery and the fan voltage supply circuit terminal 87 at the low speed fan relay and the high speed fan relay connections and verify fan activation. If the appropriate fan does not activate, test the fan voltage supply circuit for a short to ground or open/high resistance. If the circuit tests normal, test the fan ground circuit for an open/high resistance. If the circuits test normal, replace the fan.
6. Ignition ON, connect a 30A fused jumper between the relay switch voltage supply circuit terminal 30 and the fan voltage supply circuit terminal 87 at the cool/fan 1 and the cool/fan 2 relay connections and verify fan activation. If the fan does not activate, test the relay switch voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and its fuse is open, test all connected components and replace as necessary.
7. If the circuits and fans test normal, replace the relay.

Thermostat Diagnosis

Tools Required

1. J 24731 188 Tempilstick. See «Special Tools»(ref-301507-S03788199182008101700000) .
2. J 24731 206 Tempilstick. See «Special Tools»(ref-301507-S03788199182008101700000) .

The coolant thermostat can be tested using a temperature (tempil) stick. The temperature stick is a pencil-like device which has a wax material containing certain chemicals that melt at a given temperature. Temperature sticks can be used to determine a thermostat's operating range by rubbing 87°C (188°F) and 97°C (206°F) sticks on the outlet coolant pipe.

1. Use a tempilstick in order to find the opening and the closing temperatures of the thermostat. J 24731 188 tempilstick melts at 87°C (188°F). See «Special Tools»(ref-301507-S03788199182008101700000) . The thermostat should begin to open at 90°C (194°F). J 24731 206 tempilstick melts at 97°C (206°F). See «Special Tools»(ref-301507-S03788199182008101700000) . The thermostat should be fully open at 107°C (225°F).
2. Replace the thermostat if it does not operate properly between this temperature range.

1. Perform the «Diagnostic System Check - Vehicle»(ref-301515-S32423278442008101700000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-301515-S06578354042008101700000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-301515-S28090839972008101700000) provides an overview of each diagnostic category.

1. Test the engine coolant heater for an open or short to ground. If open or shorted, replace the heater.
2. If the heater tests normal, replace the coolant heater power cord.

Pressure Cap Testing

Tools Required

1. J 24460-01 Cooling System Pressure Tester. See «Special Tools»(ref-301507-S03788199182008101700000) .
2. J 42401 Radiator Cap/Surge Tank Test Adapter. See «Special Tools»(ref-301507-S03788199182008101700000) .

1. Remove the pressure cap.
2. Wash the pressure cap sealing surface with water.
3. Use the J 24460-01 (1) with J 42401 (2) in order to test the pressure cap. See «Special Tools»(ref-301507-S03788199182008101700000) .
4. Test the pressure cap for the following conditions: Pressure release when the J 24460-01 exceeds the pressure rating of the pressure cap. See «Special Tools»(ref-301507-S03788199182008101700000) . Maintain the rated pressure for at least 10 seconds. Note the rate of pressure loss.
5. Replace the pressure cap under the following conditions: The pressure cap does not release pressure which exceeds the rated pressure of the cap. The pressure cap does not hold the rated pressure.

Cooling System Leak Testing

Tools Required

1. J 24460-01 Cooling System Pressure Tester. See «Special Tools»(ref-301507-S03788199182008101700000) .
2. J 42401 Radiator Cap / Surge Tank Test Adapter. See «Special Tools»(ref-301507-S03788199182008101700000) .

1. Remove the pressure cap.
2. Test the operation of the pressure cap. Refer to «Pressure Cap Testing»(ref-301507-S20399564642008101700000) .
3. Wash the pressure cap mating surface with water.
4. Use the J 24460-01 with J 42401 in order to apply pressure to the cooling system. See «Special Tools»(ref-301507-S03788199182008101700000) . Do not exceed the pressure cap rating.
5. The cooling system should hold the rated pressure for at least 2 minutes. Observe the gage for any pressure loss.
6. Repair any leaks as required.