DTC P1626: Auto Start Request Circuit High: Notes

1. -

DTC detecting condition:

Detected when three consecutive driving cycles with fault occur.

Trouble symptom:

Auto Start Stop does not operate.

Wiring diagram:

ENGINE TYPE FB

Auto Start Stop Refer to WIRING SYSTEM>AUTO START STOP>WIRING DIAGRAM>ENGINE TYPE FB .

Courtesy of SUBARU OF AMERICA, INC.

ENGINE TYPE FA

Auto Start Stop Refer to WIRING SYSTEM>AUTO START STOP>WIRING DIAGRAM>ENGINE TYPE FA .

Courtesy of SUBARU OF AMERICA, INC.

CAUTION:

Use the check board when measuring the TCM/ECM terminal voltage and resistance.
After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. Refer to AUTO START STOP (DIAGNOSTICS)>Basic Diagnostic Procedure .

CHECK DATA MONITOR .
1. Turn the ignition switch to ON.
2. Read the data of [Restart Commanded Signal] in ECM using Subaru Select Monitor. Refer to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>DATA MONITOR .
NOTE: Start the engine and drive at 5 km/h (3 MPH) or more.

Does the display of [Restart Commanded Signal] change to [ON] while driving?

Yes : The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

No : Go to 2.
CHECK HARNESS BETWEEN ECM CONNECTOR AND TCM CONNECTOR .
1. Turn the ignition switch to OFF.
2. Disconnect the ECM connector.
3. Disconnect the TCM connector.
4. Measure the resistance between ECM connector and TCM connector.
  Connector & terminal
  
  ENGINE TYPE FB
  
  (E53) No. 36 - (T21) No. 23:
  
  ENGINE TYPE FA
  
  (E51) No. 19 - (B67) No. 23:
Is the resistance less than 1 Ω?

Yes : Go to 3.

No : Repair the open circuit of harness and poor contact of coupling connector between ECM connector and TCM connector.
CHECK DATA MONITOR .
1. Connect the ECM connector.
2. Turn the ignition switch to ON.
3. Read the data of [Restart Commanded Signal] in ECM using Subaru Select Monitor. Refer to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>DATA MONITOR .
4. Short the terminal No. 23 of TCM connector to ground.
Does the display of [Restart Commanded Signal] change to [ON]?

Yes : Check for poor contact of ECM connector. Replace the ECM if no fault is found. Refer to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>ENGINE CONTROL MODULE (ECM) . Refer to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>ENGINE CONTROL MODULE (ECM) .

No : Check for poor contact of TCM connector. Replace the TCM if no fault is found. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>TRANSMISSION CONTROL MODULE (TCM) . Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>TRANSMISSION CONTROL MODULE (TCM) .