DTC P0597-12: Thermostat Heater Control Circuit Short to Battery [11/2021 - 03/2022]: Procedure
WARNING: This page is about a different car, the 2025 Lexus NX 250, 2024 Lexus NX 250, 2023 Lexus NX 250, and 2022 Lexus NX 250. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK HARNESS AND CONNECTOR (WATER INLET WITH THERMOSTAT SUB-ASSEMBLY - ECM)
- Disconnect the water inlet with thermostat sub-assembly connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition V4-2 or B50-7 (HTHM) - other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE ECM. Refer to REMOVAL [11/2021 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR