DTC P0597-14: Thermostat Heater Control Circuit Short to Ground or Open [06/2020 - 08/2020]: Procedure
- CHECK TERMINAL VOLTAGE (POWER SOURCE OF THERMOSTAT HEATER (WATER INLET WITH THERMOSTAT SUB-ASSEMBLY))
*a Front view of wire harness connector
(to Water Inlet with Thermostat Sub-assembly)- Disconnect the thermostat heater (water inlet with thermostat sub-assembly) connector.
- Turn the ignition switch to ON.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition F5-1 (ETM+) - Body ground Ignition switch ON 11 to 14 V Result
Proceed to OK NG
Result:
NG
See step 4
Result:
OK
See step 2
- INSPECT THERMOSTAT HEATER (WATER INLET WITH THERMOSTAT SUB-ASSEMBLY)
- Inspect the thermostat heater (water inlet with thermostat sub-assembly).
Refer to INSPECTION [11/2018 - 12/2021]
Result
Proceed to OK NG
Result:
NG
REPLACE THERMOSTAT HEATER (WATER INLET WITH THERMOSTAT SUB-ASSEMBLY)
Refer to REMOVAL [10/2019 - 08/2020]
Result:
OK
See step 3
- Inspect the thermostat heater (water inlet with thermostat sub-assembly).
- CHECK HARNESS AND CONNECTOR (THERMOSTAT HEATER (WATER INLET WITH THERMOSTAT SUB-ASSEMBLY) - ECM)
- Disconnect the thermostat heater (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 F5-2 (ETM-) - C45-7 (HTHM) Always Below 1 Ω F5-2 (ETM-) or C45-7 (HTHM) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE ECM
Refer to REMOVAL [02/2019 - 08/2020]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- INSPECT EFI-MAIN NO. 2 RELAY
- Inspect the EFI-MAIN NO. 2 relay.
Refer to PROCEDURE - Step 2
Result
Proceed to OK NG
Result:
NG
REPLACE EFI-MAIN NO. 2 RELAY
Result:
OK
See step 5
- Inspect the EFI-MAIN NO. 2 relay.
- CHECK TERMINAL VOLTAGE (POWER SOURCE OF EFI-MAIN NO. 2 RELAY)
*1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly *2 EFI-MAIN NO. 2 Relay - Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition 3 (EFI-MAIN NO. 2 relay) - Body ground Always 11 to 14 V Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - EFI-MAIN NO. 2 RELAY)
Result:
OK
See step 6
- CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 2 RELAY - BODY GROUND)
- Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 1 (EFI-MAIN NO. 2 relay) - Body ground Always Below 1 Ω Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 7
- CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 2 RELAY - THERMOSTAT HEATER (WATER INLET WITH THERMOSTAT SUB-ASSEMBLY))
- Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
- Disconnect the thermostat heater (water inlet with thermostat sub-assembly) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 5 (EFI-MAIN NO. 2 relay) - F5-1 (ETM+) Always Below 1 Ω 5 (EFI-MAIN NO. 2 relay) or F5-1 (ETM+) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN NO. 1 RELAY - EFI-MAIN NO. 2 RELAY)
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR