DTC P0597-14: Thermostat Heater Control Circuit Short to Ground or Open [12/2019 - 10/2022]: Procedure

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1. Disconnect the water inlet with thermostat sub-assembly connector.
2. Turn the ignition switch to ON.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   C42-1 (ETM+) - Body ground	Ignition switch ON	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN RELAY - WATER INLET WITH THERMOSTAT SUB-ASSEMBLY) 

Result: 

OK 

See step  2

Refer to INSPECTION [12/2019 - 10/2022]

Result

Result: 

NG 

REPLACE WATER INLET WITH THERMOSTAT SUB-ASSEMBLY. Refer to  REMOVAL [12/2019 - 10/2022] 

Result: 

OK 

See step  3

1. Disconnect the water inlet with thermostat sub-assembly connector.
2. Disconnect the ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C42-2 (ETM-) - C54-64 (PTCR)	Always	Below 1 Ω
   C42-2 (ETM-) or C54-64 (PTCR) - Body ground and other terminals	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Clear the DTC.

   Powertrain > Engine > Clear DTCs 

2. Turn the ignition switch off and wait for at least 30 seconds.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  5

1. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
2. Read the DTCs.

   Powertrain > Engine > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are not output	A
   DTC P0597-14 is output	B

Result: 

A 

CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [12/2019 - 10/2022] 

Result: 

B 

REPLACE ECM. Refer to  REMOVAL [12/2019 - 09/2020]  , or refer to  REMOVAL [09/2020 - 10/2022]