Inspection Procedure

HINT:

Although each DTC title says "Coolant Flow Control Valve", these DTCs are related to the water valve.
CHS stands for Coolant Heat Storage.

CAUTION: Be careful when replacing any part in the system or changing the coolant because the coolant in the heat storage tank is hot even if the engine is cold.

HINT:

If DTCs P1121 and P1150 are detected simultaneously, there may be malfunction in the water valve system.
If DTC P1121 is detected, coolant passages may be clogged.
To check the coolant heat storage (CHS) system, the ECM may cause the water pump of the CHS system to operate 5 hours after the power switch has been turned OFF.
Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P1121)

Connect the intelligent tester to the DLC3.
Turn the power switch ON (IG).
Turn the tester ON.
Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

Read DTCs.

Result

RESULT REFERENCE

Display (DTC Output)	Proceed to
P1121	A
P1121 and other DTCs	B

HINT:

If any other codes besides P1121 are output, perform troubleshooting for those DTCs first.

B: Go to DTC CHART

A: Go to Next Step

PERFORM ACTIVE TEST BY INTELLIGENT TESTER

Connect the intelligent tester to the DLC3.
Turn the power switch ON (IG).
Turn the tester ON.
Put the engine in inspection mode (see SFI SYSTEM ).
Start the engine and warm it up.
Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / WATER FLW VLV3, WATER FLW VLV4 or WATER FLW VLV5.

Measure the voltage between terminals WBAD and E2 of the ECM connector.

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION

Tester Operation	Specified Condition
"WATER FLW VLV 3" ON	Approximately 2.5 V
"WATER FLW VLV 4" ON	Approximately 3.5 V
"WATER FLW VLV 5" ON	Approximately 4.5 V

NG: REPLACE WATER W/BRACKET VALVE ASSEMBLY

OK: Go to Next Step

CHECK COOLING SYSTEM (CHECK FOR CLOGGING IN THE COOLANT SYSTEM)
OK: Coolant passages are not clogged.

NG: REPAIR OR REPLACE COOLING SYSTEM

OK: REPLACE ECM