DTC P0113 (Flash Code 22) Intake Air Temperature Sensor Circuit High (RZ4E-TC)

1. Engine control system check

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

2. IAT sensor signal voltage check

1) Connect the scan tool.

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

3) Start the engine.

4) Observe the Intake Air Temperature (IAT) Sensor parameter on the scan tool. Is the Intake Air Temperature (IAT) Sensor parameter more than or equal to the specified value?

Value: 4.8 V

Yes

=>Go to IAT sensor signal output voltage check.

Go to Intermittent conditions of engine.

Refer to "202.Engine 15D.Symptom(RZ4E-TC) intermittent conditions of engine".

3. IAT sensor signal output voltage check

1) Turn OFF the ignition switch.

2) Disconnect the MAF and IAT sensor harness connector (C39).

3) Turn ON the ignition switch.

4) Measure the voltage between the IAT sensor signal circuit (pin 4 of C39) and the body ground with a DMM.

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.).

Value: 4.5 to 5.5 V

The reading is more than the specified value.

=>Go to Inspection for short to power supply in IAT sensor signal circuit.

The reading is within the specified range.

=>Go to IAT sensor signal voltage check using fused jumper wire.

The reading is less than the specified value.

=>Go to Inspection for open circuit in IAT sensor signal circuit.

4. IAT sensor signal voltage check using fused jumper wire

1) Connect a fused jumper wire between the signal circuit and the low reference circuit of the IAT sensor (pins 4 and 5 of C39).

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.).

2) Observe the Intake Air Temperature (IAT) Sensor parameter on the scan tool. Is the Intake Air Temperature (IAT) Sensor parameter less than or equal to the specified value?

Value: 0.1 V

Yes

=>Go to Inspection for short to 5 V reference in IAT sensor signal circuit.

=>Go to Inspection for open circuit in IAT sensor low reference circuit.

5. Inspection for short to power supply in IAT sensor signal circuit

1) Inspect the IAT sensor signal circuit between the ECM (pin 72 of C7) and the MAF and IAT sensor (pin 4 of C39) for a short to the battery power supply circuit or a short to the ignition power supply circuit. Is the result normal?

Note

The IAT sensor may be damaged if the sensor signal circuit is shorted to the power supply.

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

=>Go to ECM replacement.

Repair the circuit as necessary.

=>Go to Repair verification.

6. Inspection for open circuit in IAT sensor signal circuit

1) Inspect the IAT sensor signal circuit between the ECM (pin 72 of C7) and the MAF and IAT sensor (pin 4 of C39) for an open circuit or 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.).

Yes

=>Go to ECM harness connector inspection.

Repair the circuit as necessary.

=>Go to Repair verification.

7. Inspection for open circuit in IAT sensor low reference circuit

1) Inspect the IAT sensor low reference circuit between the ECM (pin 60 of C7) and the MAF and IAT sensor (pin 5 of C39) for an open circuit or high resistance. Is the result normal?

Caution

The IAT sensor shares the low reference circuit with other sensors. A malfunction in the low reference circuit may set DTCs on sensors that share this 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

=>Go to ECM harness connector inspection.

Repair the circuit as necessary.

=>Go to Repair verification.

8. Inspection for short to 5 V reference in IAT sensor signal circuit

1) Inspect the IAT sensor signal circuit between the ECM (pin 72 of C7) and the MAF and IAT sensor (pin 4 of C39) for a short to the 5 V reference circuit. 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.).

Yes

=>Go to MAF and IAT sensor harness connector inspection.

Repair the circuit as necessary.

=>Go to Repair verification.

9. MAF and IAT sensor harness connector inspection

1) Inspect for poor connections at the MAF and IAT sensor harness connector (pins 4 and 5 of C39). Is the connection status 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.).

Yes

Replace the MAF and IAT sensor.

Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) MAF and IAT sensor removal".

Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) MAF and IAT sensor installation".

=>Go to Repair verification.

Repair the connections as necessary.

=>Go to Repair verification.

10. ECM harness connector inspection

1) Inspect for poor connections at the ECM harness connector (pins 60 and 72 of C7). Is the connection status 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.).

Yes

=>Go to ECM replacement.

Repair the connections as necessary.

=>Go to Repair verification.

11. ECM replacement

Note

Perform programming after replacing the ECM.

Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) ECM removal".

Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) ECM installation".

Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) ECM setting".

Procedure completion

=>Go to Repair verification.

12. Repair verification

1) Clear the DTC with a scan tool.

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

3) Start the engine.

4) Operate the vehicle under the conditions for running the DTC.

5) Observe the DTC information with a scan tool.