Engine Control System - 2.0L: Diagnosis Kia Optima III

ECM Problem Inspection Procedure

1. TEST ECM GROUND CIRCUIT: Measure resistance between ECM and chassis ground using the backside of ECM harness connector as ECM side check point. If the problem is found, repair it. Specification: Below 1ohms
2. TEST ECM CONNECTOR: Disconnect the ECM connector and visually check the ground terminals on ECM side and harness side for bent pins or poor contact pressure. If the problem is found, repair it.
3. If problem is not found in Step 1 and 2, the ECM could be faulty. If so, make sure there were no DTC's before swapping the ECM with a new one, and then check the vehicle again. If DTC's were found, examine this first before swapping ECM.
4. RE-TEST THE ORIGINAL ECM: Install the original ECM (may be broken) into a known-good vehicle and check the vehicle. If the problem occurs again, replace the original ECM with a new one. If problem does not occur, this is intermittent problem. Refer to "Intermittent Problem Inspection Procedure" in «BASIC INSPECTION PROCEDURE»(ref-429551-S35236120592011101500000) .

Inspection

1. Connect the GDS on the Data Link Connector (DLC).
2. Measure the output voltage of the MAPS at idle and IG ON.

Specification: Refer to SPECIFICATION .

Scheme 94

Scheme 95

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Disconnect the manifold absolute pressure sensor connector (A).
3. Remove the installation bolts (B), and then remove the sensor from the surge tank. MAPS #1 MAPS #2

1. Turn the ignition switch OFF.
2. Disconnect the IATS connector.
3. Measure resistance between the IATS terminals 3 and 4.
4. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

1. Turn the ignition switch OFF.
2. Remove the ECTS. Refer to «REMOVAL»(ref-429552-S11894207152011101500000) .
3. After immersing the thermistor of the sensor into engine coolant, measure resistance between the ECTS terminals 3 and 4.
4. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

Scheme 96

Scheme 97

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Disconnect the engine coolant temperature sensor connector (A).
3. Remove the spring clip (A), and then pull the sensor from the water temperature control assembly. CAUTION: Note that engine coolant may be flowed out from the water temperature control assembly when removing the sensor.
4. Supplement the engine coolant. Refer to «COOLING SYSTEM»(ref-429534) .

1. Check the signal waveform of the CMPS and CKPS using the GDS.

Specification: Refer to " WAVE FORM .

Scheme 98

Scheme 99

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Disconnect the crankshaft position sensor connector (A).
3. Remove the protector (A).
4. Remove the installation bolt (A), and then remove the crankshaft position sensor.

Scheme 100

1. Check the signal waveform of the CMPS and CKPS using the GDS.

Specification: Refer to WAVE FORM .

1. Turn the ignition switch OFF.
2. Disconnect the HO2S connector.
3. Measure resistance between the HO2S terminals 4 and 5 (B1/S1).
4. Measure resistance between the HO2S terminals 3 and 4 (B1/S2).
5. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

1. Connect the GDS on the Data Link Connector (DLC).
2. Measure the output voltage of the RPS at idle and various engine speed.

VOLTAGE SPECIFICATION CHART

1. Turn the ignition switch OFF.
2. Disconnect the OTS connector.
3. Remove the OTS.
4. After immersing the thermistor of the sensor into engine coolant, measure resistance between the OTS terminals 1 and 2.
5. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

1. Connect the GDS on the Data Link Connector (DLC).
2. Turn the ignition switch ON.
3. Measure the output voltage of the APS 1 and 2 at C.T and W.O.T.

Specification: Refer to SPECIFICATION .

1. Connect the GDS on the Data Link Connector (DLC).
2. Measure the output voltage of the FTPS.

Specification: Refer to SPECIFICATION .

Scheme 101

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Remove the fuel pump service cover (A) in the trunk.
3. Disconnect the fuel tank pressure sensor connector (A), and then remove the fuel tank pressure sensor.

Scheme 102

1. Turn the ignition switch OFF.
2. Disconnect the injector connector.
3. Measure resistance between the injector terminals 1 and 2.
4. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

1. Turn the ignition switch OFF.
2. Disconnect the PCSV connector.
3. Measure resistance between the PCSV terminals 1 and 2.
4. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

Scheme 103

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Disconnect the purge control solenoid valve connector (A).
3. Disconnect the vapor hoses (B) from the purge control solenoid valve.
4. Remove the valve from the bracket in the direction of the arrow.

Scheme 104

1. Turn the ignition switch OFF.
2. Disconnect the OCV connector.
3. Measure resistance between the OCV terminals 1 and 2.
4. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Disconnect the fuel pressure regulator valve connector.
3. Measure resistance between the fuel pressure regulator valve terminals 1 and 2.
4. Check that the resistance is within the specification.

Specification: Refer to SPECIFICATION .

1. Turn the ignition switch OFF.
2. Disconnect the RCV control solenoid valve connector.
3. Measure resistance between the valve terminals 1 and 2.
4. Check that the resistance is within the specification. Specification: Refer to «SPECIFICATION»(ref-429552-S15361024982011101500000) .

1. Turn the ignition switch OFF.
2. Disconnect the CCV connector.
3. Measure resistance between the CCV terminal 1 and 2.
4. Check that the resistance is within the specification. Specification: Refer to «SPECIFICATION»(ref-429552-S08357078762011101500000) .
5. Disconnect the vapor hose connected with the canister from the CCV.
6. Connect a vacuum pump to the nipple.
7. Ground the CCV control line and apply battery voltage to the CCV power supply line.
8. Apply vacuum and check the valve operation.

Specification: Vacuum maintained

Scheme 105

Scheme 106

Scheme 107

1. Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2. Lift the vehicle.
3. Disconnect the canister close valve connector (A).
4. Disconnect the ventilation hose (B).
5. Remove the fuel tank air filter after removing 2 bolts (C).
6. Release the lever (A) and then rotate the canister close valve (B) in the direction of the arrow in the illustration.
7. Remove CCV from the fuel tank air filter after coinciding installation parts (A, B).

Scheme 108