Circuit figure

Fig 1: Line Pressure Control Solenoid Assembly Circuit Diagram (SLT)

Courtesy of SUBARU OF AMERICA, INC.

Inspection steps

1. Wiring harness and connector check
   1. Disconnect the connector A18 of the transmission control computer ASSY.
   2. Measure the resistance between the terminals. Resistance
      RESISTANCE SPECIFICATIONS
      
      

      Inspection terminals	Inspection conditions	Standard value
      A18-4 (SLT+) - A18-9 (SLT-)	20°C	5.0 to 5.6Ω

   3. Connect the connector A18 of the transmission control computer ASSY.

   NG: go to step  4.

   OK: Go to next step.

2. Check wiring harness and connector (transmission wire - transmission control computer)
   1. Disconnect the connector A18 of the transmission control computer ASSY.
   2. Disconnect the connector L4 of the transmission wire.
   3. Measure the resistance of the vehicle side connector. (For terminal arrangement, refer to ECM terminal arrangement .)
      RESISTANCE SPECIFICATIONS
      
      

      Inspection terminals	Inspection conditions	Standard value
      A18-4 (SLT+) - L4-13 (SLT+)	Always	Less than 1 Ω

      A18-9 (SLT-) - L4-5 (SLT-)

      Always

      Less than 1 Ω

   4. Measure the voltage between the terminals.
      VOLTAGE SPECIFICATIONS
      
      

      Inspection terminals	Inspection conditions	Standard value
      A18-4 (SLT+) - chassis ground	IG ON	1 V or less
      A18-9 (SLT-) - chassis ground	IG ON	1 V or less

   5. Connect the connector L4 of the transmission wire.
   6. Connect the connector A18 of the transmission control computer ASSY.

   NG: Repair or replacement of wiring harness or connector

   OK: Go to next step.

3. Replacement of transmission control computer ASSY
   1. Replace the transmission control computer ASSY. (Refer to Transmission control computer ASSY )

   Next: AT unit correction

4. Check of line pressure control solenoid ASSY (SLT) unit
   1. Check the line pressure control solenoid ASSY (SLT) unit. (Refer to Neutral start switch ASSY )

   NG: Repair or replacement of transmission valve body ASSY (refer to Transmission valve body ASSY )

   OK: Repair or replacement of transmission wire (refer to Transmission wire )