DTC P1404 (Flash Code 45) Exhaust Gas Recirculation (EGR) 1 Closed Position Performance (RZ4E-TC)

1. Engine control system check

Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) Diagnostic system check-engine controls".

2. Prioritized DTC check

1) Connect the scan tool.

2) Turn OFF the ignition switch for 30 seconds or more.

3) Start the engine.

4) Observe the DTC information with a scan tool. Is DTC P042E set at the same time?

Yes

Go to DTC P042E diagnosis.

Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) DTC P042E (Flash Code 45) Exhaust Gas Recirculation (EGR) Closed Position Performance".

=>Go to EGR valve inspection.

3. EGR valve inspection

1) Remove the EGR valve from the engine.

Refer to "1.Engine 1H.Aux. Emission Control Devices(RZ4E-TC) EGR removal".

2) Inspect the EGR valve for the following. Is the result normal?

The flow in the EGR valve is restricted by foreign material.
Excessive deposits in the valve
Bent valve shaft

Yes

=>Go to Inspection of EGR valve circuit.

Repair or replace as necessary.

=>Go to Repair verification.

4. Inspection of EGR valve circuit

1) Inspect for poor connections at the EGR valve harness connector (pins 1, 2, 3, 4, and 6 of E49). Is the connection status normal?

2) Inspect for poor connections at the ECM harness connector (pins 11, 14, 22, 28, and 30 of E4). Is the connection status normal?

3) Inspect the circuit between the ECM (pins 11, 14, 22, 28, and 30 of E4) and the EGR valve (pins 1, 2, 3, 4, and 6 of E49) for high resistance. Is the result normal?

Refer to "RHD Engine Control (RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Engine Control (RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

4) Are all of the results normal?

Yes

=>Go to Inspection for short circuit in EGR motor circuit.

Repair the circuit or connection as necessary.

=>Go to Repair verification.

5. Inspection for short circuit in EGR motor circuit

1) Inspect the motor circuit between the ECM (pins 22 and 30 of E4) and the EGR valve (pins 4 and 6 of E49) for the following. Is the result normal?

Short to ground
Short to the battery power supply circuit or short to the ignition power supply circuit
Short together between motor circuits
Short to position sensor circuit

Refer to "RHD Engine Control (RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Engine Control (RZ4E)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

Replace the EGR valve.

Refer to "1.Engine 1H.Aux. Emission Control Devices(RZ4E-TC) EGR removal".

Refer to "1.Engine 1H.Aux. Emission Control Devices(RZ4E-TC) EGR installation".

=>Go to Repair verification.

Repair or replace as necessary.

=>Go to Repair verification.

6. Repair verification

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch for 30 seconds or more.

3) Turn ON the ignition switch.

4) Observe the DTC information with a scan tool.