Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) Diagnostic system check-engine controls".
1) Connect the scan tool.
2) Turn OFF the ignition switch for 30 seconds or more.
3) Start the engine.
4) Observe the Mass Air Flow (MAF) Sensor parameter on the scan tool. Is the Mass Air Flow (MAF) Sensor parameter less than or equal to the specified value?
Value: 0.1 V
Yes
=>Go to Inspection for open circuit in MAF sensor power supply circuit.
No
Go to Intermittent conditions of engine.
Refer to "202.Engine 15D.Symptom(RZ4E-TC) intermittent conditions of engine".
1) Turn OFF the ignition switch.
2) Disconnect the MAF and IAT sensor harness connector (C39).
3) Connect a test lamp between the ignition power supply circuit (pin 1 of C39) and the body ground.
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) Turn ON the ignition switch. Does the test lamp illuminate?
Yes
=>Go to MAF sensor signal voltage check using fused jumper wire.
No
Repair the open circuit or high resistance in the ignition power supply circuit between the ENGINE 15A fuse and the MAF and IAT sensor (pin 1 of C39). Inspect the ENGINE 15A fuse first.
1) Connect a fused jumper wire between the ignition power supply circuit and the signal circuit (pins 1 and 3 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 Mass Air Flow (MAF) Sensor parameter on the scan tool. Is the Mass Air Flow (MAF) Sensor parameter more than or equal to the specified value?
Value: 4.9 V
Yes
=>Go to MAF and IAT sensor harness connector inspection.
No
=>Go to Inspection for open circuit and short circuit in MAF sensor signal circuit.
1) Inspect the MAF sensor signal circuit between the ECM (pin 69 of C7) and the MAF and IAT sensor (pin 3 of C39) for the following. 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.
No
Repair the circuit as necessary.
1) Inspect for poor connections at the MAF and IAT sensor harness connector (pins 1 and 3 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".
No
Repair the connections as necessary.
1) Inspect for poor connections at the ECM harness connector (pin 69 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
No
Repair the connections as necessary.
Note
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
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.