DTC P16B3-19: Multi Flow Control Valve Motor Circuit Current Above Threshold [10/2022 - ]: Procedure
WARNING: This page is about a different car, the 2025 Lexus RX 350, 2024 Lexus RX 350, and 2023 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
- INSPECT WATER CONTROL VALVE
Refer to INSPECTION [10/2022 - ]
Result
Proceed to OK NG Result:
NG
REPLACE WATER CONTROL VALVE. Refer to REMOVAL [10/2022 - ]
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (WATER CONTROL VALVE - ECM)
Pre-procedure1
- Disconnect the water control valve connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result B41-5 (FCM+) or B27-3 (FCM+) - Other terminals Always 10 kΩ or higher kΩ B41-4 (FCM-) or B27-4 (FCM-) - Other terminals Always 10 kΩ or higher kΩ Result
Proceed to OK NG
Post-procedure1
- None.
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- INSPECT ECM (INTERNAL CIRCUIT)
Pre-procedure1
- Disconnect the water control valve connector.
- Inspect the ECM using an oscilloscope.
- Turn the ignition switch to ON.
- While the ignition switch to ON, check the waveform the terminals of the water control valve connector.
*a Front view of wire harness connector
(to Water Control Valve)*b Waveform of FCM+ terminal and FCM- terminal during fail-safe ECM Terminal Name B41-5 (FCM+) - B41-4 (FCM-) Tester Range 2 V/DIV., 1 ms./DIV. Condition Ignition switch ON - While the ignition switch to ON, check the waveform between the FCM+ terminal and FCM- terminal during fail-safe.
Standard
25% duty waveform is output
HINT:
- Check the operation circuit of the ECM by checking the waveform during fail-safe.
- Because fail-safe is prohibited when the ambient temperature is 0°C (32°F) or less, work in a location where the ambient temperature is 5°C (41°F) or higher.
- DTCs may be stored during this inspection. Check for DTCs and clear them using the GTS.
Result
Proceed to OK NG
Post-procedure1
- None.
Result:
OK
REPLACE WATER CONTROL VALVE. Refer to REMOVAL [10/2022 - ]
Result:
NG
REPLACE ECM. Refer to REMOVAL [10/2022 - ]