Code 2, Open Isolation Solenoid Circuit

Turn ignition off. Disconnect RWAL ECM connector. Measure resistance between ECM harness connector terminal No. 1 and ground. See Fig 1 .

Fig 1: Identifying RWAL ECM, Pressure Limit Valve & Power Relay Connector Terminals
Courtesy of SUZUKI OF AMERICA CORP.
If resistance reading is 3-6 ohms, check RWAL ECM connections. If connections are okay, replace RWAL ECM.
If resistance reading is more than 6 ohms, disconnect pressure limit valve connector. Measure resistance between limit valve isolation solenoid terminal No. 1 and ground terminal No. 4. See Fig 2 .

Fig 2: Identifying Pressure Limit Valve & Related Terminals
Courtesy of SUZUKI OF AMERICA CORP.
If resistance is now 3-6 ohms, repair open in harness Green or Black wire. If resistance is more than 6 ohms, isolation solenoid winding is open. Replace pressure limit valve.