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 DTC information with a scan tool. Is DTC P0651 set at the same time?
Yes
Go to DTC P0651 diagnosis.
Refer to "51.Engine Control 1A.Troubleshooting(RZ4E-TC) DTC P0651 (Flash Code 56) Sensor Reference Voltage 2 Circuit".
No
=>Go to Barometric pressure sensor signal voltage check.
1) Observe the Barometric Pressure (BARO) Sensor parameter on the scan tool. Is the Barometric Pressure (BARO) Sensor parameter less than or equal to the specified value?
Value: 0.5 V
Yes
=>Go to Barometric pressure sensor 5 V reference voltage check.
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 barometric pressure sensor harness connector (C37).
3) Turn ON the ignition switch.
4) Measure the voltage between the barometric pressure sensor 5 V reference circuit (pin 3 of C37) and the body ground with a DMM. Is the voltage more than or equal to the specified value?
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 V
Yes
=>Go to Barometric pressure sensor signal voltage check using fused jumper wire.
No
=>Go to Inspection for open circuit in barometric pressure sensor 5 V reference circuit.
1) Connect a fused jumper wire between the barometric pressure sensor 5 V reference circuit and the signal circuit (pins 2 and 3 of C37).
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 Barometric Pressure (BARO) Sensor parameter on the scan tool. Is the Barometric Pressure (BARO) Sensor parameter more than or equal to the specified value?
Value: 4.5 V
Yes
=>Go to Barometric pressure sensor harness connector inspection.
No
=>Go to Inspection for open circuit and short circuit in barometric pressure sensor signal circuit.
1) Inspect the 5 V reference circuit between the ECM (pin 61 of C7) and the barometric pressure sensor (pin 3 of C37) for an open circuit or high resistance. Is the result normal?
Caution
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 the signal circuit between the ECM (pin 71 of C7) and the barometric pressure sensor (pin 2 of C37) 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 barometric pressure sensor harness connector (pins 2 and 3 of C37). 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 barometric pressure sensor.
Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) barometric pressure sensor removal".
Refer to "1.Engine 1Z.Engine Electrical Control(RZ4E-TC) barometric pressure sensor installation".
No
Repair the connections as necessary.
1) Inspect for poor connections at the ECM harness connector (pins 61 and 71 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.