DTC P16B3-19: Multi Flow Control Valve Motor Circuit Current Above Threshold [11/2021 - ]: Procedure
WARNING: This page is about a different car, the 2025 Lexus NX 350, 2024 Lexus NX 350, 2023 Lexus NX 350, and 2022 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.
- INSPECT WATER CONTROL VALVE
- Inspect the water control valve.
Refer to INSPECTION [11/2021 - ]
Result
Proceed to OK NG
Result:
NG
REPLACE WATER CONTROL VALVE. Refer to REMOVAL [11/2021 - ]
Result:
OK
See step 2
- Inspect the water control valve.
- CHECK HARNESS AND CONNECTOR (WATER CONTROL VALVE - ECM)
- 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 B69-5 (FCM+) or B49-3 (FCM+) - Other terminals Always 10 kΩ or higher B69-4 (FCM-) or B49-4 (FCM-) - Other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- INSPECT ECM (INTERNAL CIRCUIT)
*a Front view of wire harness connector
(to Water Control Valve)*b Waveform of FCM+ terminal and FCM- terminal during fail-safe - 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.
ECM Terminal Name B69-5 (FCM+) - B69-4 (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
Result:
OK
REPLACE WATER CONTROL VALVE. Refer to REMOVAL [11/2021 - ]
Result:
NG
REPLACE ECM. Refer to REMOVAL [11/2021 - ]