DTC P26A3: Engine Coolant Bypass Valve "A" Range/Performance: Notes

1. -

DTC detecting condition:

Detected when two consecutive driving cycles with fault occur.

Trouble symptom:

Coolant temperature rises slowly
Poor acceleration

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

CHECK THERMO-CONTROL VALVE ASSEMBLY MOTOR .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance between ECM connectors.
  Connector and terminal
  
  (E53) No. 82 - (E53) No. 91:
  
  Is the resistance 1 MΩ or more?
  
  Yes : Go to 2 .
  
  No : Go to 3 .
CHECK HARNESS BETWEEN ECM AND THERMO-CONTROL VALVE ASSEMBLY CONNECTOR (OPEN) .
1. Disconnect the connector from the thermo-control valve assembly.
2. Measure the resistance between ECM connector and thermo-control valve assembly connector.
  Connector and terminal
  
  (E53) No. 82 - (E119) No. 5:
  
  (E53) No. 91 - (E119) No. 4:
  
  Is the resistance 1 MΩ or more?
  
  Yes : Repair the open circuit of the harness between the ECM connector and thermo-control valve assembly connector.
  
  No : Replace the thermo-control valve assembly. Ref. to COOLING (H4DO)>THERMO CONTROL VALVE ASSEMBLY .
CHECK THERMO-CONTROL VALVE ASSEMBLY OPENING ANGLE SENSOR .
1. Using the Subaru Select Monitor, select [Coolant Circulation Valve Control] of [Active Test].
  NOTE: For detailed operation procedures, refer to the "Active Test". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>ACTIVE TEST .
2. Adjust the target value of [Coolant Circulation Valve Control] to set the value of [Coolant Circulation Valve Target Angle] to 79 deg.
3. Read the value of [Coolant Circulation Valve Actual Angle].
  Is the value of [Coolant Circulation Valve Actual Angle] between 73.7 deg - 84.3 deg within seven seconds after setting [Coolant Circulation Valve Target Angle]?
  
  Yes : Go to 4 .
  
  No : Replace the thermo-control valve assembly. Ref. to COOLING (H4DO)>THERMO CONTROL VALVE ASSEMBLY .
CHECK THERMO-CONTROL VALVE ASSEMBLY OPENING ANGLE SENSOR .
1. Adjust the target value of [Coolant Circulation Valve Control] to set the value of [Coolant Circulation Valve Target Angle] to -83 deg.
2. Read the value of [Coolant Circulation Valve Actual Angle].
  Is the value of [Coolant Circulation Valve Actual Angle] between -77.7 deg - -88.3 deg within seven seconds after setting [Coolant Circulation Valve Target Angle]?
  
  Yes : Even if DTC is detected, the thermo-control valve assembly has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.
  
  No : Replace the thermo-control valve assembly. Ref. to COOLING (H4DO)>THERMO CONTROL VALVE ASSEMBLY .