DTC P0651 (Flash Code 56) Sensor Reference Voltage 2 Circuit (RZ4E-TC)

1. Engine control system check

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

2. Current 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 a DTC set?

Yes

=>Go to CMP 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".

3. CMP sensor 5 V reference voltage check

1) Turn OFF the ignition switch.

2) Disconnect the CMP sensor harness connector (E50).

3) Turn ON the ignition switch.

4) Measure the voltage between the CMP sensor 5 V reference circuit (pin 3 of E50) 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 5 V reference circuit.

The reading is within the specified range.

Replace the CMP sensor.

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

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

=>Go to Repair verification.

The reading is less than the specified value.

=>Go to FRP sensor 5 V reference voltage check.

4. FRP sensor 5 V reference voltage check

1) Turn OFF the ignition switch.

2) Disconnect the FRP sensor harness connector (E47).

3) Turn ON the ignition switch.

4) Measure the voltage between the CMP sensor 5 V reference circuit (pin 3 of E50) 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

Replace the FRP sensor.

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

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

=>Go to Repair verification.

No

=>Go to Barometric pressure sensor 5 V reference voltage check.

5. Barometric pressure sensor 5 V reference voltage check

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 CMP sensor 5 V reference circuit (pin 3 of E50) 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

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".

=>Go to Repair verification.

No

=>Go to Accelerator pedal position sensor 2, 5 V reference voltage check.

6. Accelerator pedal position sensor 2, 5 V reference voltage check

1) Turn OFF the ignition switch.

2) Disconnect the accelerator pedal position sensor harness connector (C67).

3) Turn ON the ignition switch.

4) Measure the voltage between the CMP sensor 5 V reference circuit (pin 3 of E50) 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

Replace the accelerator pedal.

Refer to "1.Engine 1I.Speed Control Systems(RZ4E-TC) accelerator pedal removal".

Refer to "1.Engine 1I.Speed Control Systems(RZ4E-TC) accelerator pedal installation".

=>Go to Repair verification.

No

=>Go to Inspection for short to ground in 5 V reference circuit.

7. Inspection for short to ground in 5 V reference circuit

1) Inspect 5 V reference circuit 2 between the ECM (pin 61 of C7) and the following components for a short to ground or a short to the low 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.).

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) Inspect 5 V reference circuit 5 between the ECM (pin 6 of E4) and the following components for a short to ground or a short to the low 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.).

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.).

3) Are all of the results normal?

Yes

=>Go to ECM replacement.

No

Repair the circuit as necessary.

=>Go to Repair verification.

8. Inspection for short to power supply in 5 V reference circuit

1) Inspect 5 V reference circuit 2 between the ECM (pin 61 of C7) and the following components for a short to the battery power supply circuit or a short to the ignition power supply 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.).

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) Inspect 5 V reference circuit 5 between the ECM (pin 6 of E4) and the following components for a short to the battery power supply circuit or a short to the ignition power supply 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.).

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.).

3) Are all of the results normal?

Yes

=>Go to ECM replacement.

No

Repair the circuit as necessary.

=>Go to Repair verification.

9. ECM replacement

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.

10. 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.