DTC P0787: Shift / Timing Solenoid Low (Shift Solenoid Valve ST); DTC P0788: Shift / Timing Solenoid High (Shift Solenoid Valve ST): Procedure

WARNING: This page is about a different car, the 2011 Toyota Matrix. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT TRANSMISSION WIRE (ST)

Disconnect the transmission wire connector from the transaxle.

Fig 1: Inspecting B37 Transmission Wire (ST) Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
2 - Body ground	20°C (68°F)	11 to 15 Ω

NG → See step 4

OK: Go to next step

CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)

Connect the transmission wire connector to the transaxle.

Fig 2: Checking B29 ECM Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the ECM connectors.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
B29-59 (ST) - Body ground	20°C (68°F)	11 to 15 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 3

REPLACE ECM (for 2ZR-FE). Refer to REMOVAL

INSPECT SHIFT SOLENOID VALVE ST

Remove the shift solenoid valve ST.

Fig 3: Checking Resistance Of ST Shift Solenoid Valve & Operation
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
Solenoid Connector (ST) - Solenoid Body (ST)	20°C (68°F)	11 to 15 Ω

Connect the positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.
OK

The solenoid makes an operating sound.

NG → See step 6

OK → See step 5

REPAIR OR REPLACE TRANSMISSION WIRE. Refer to REMOVAL
REPLACE SHIFT SOLENOID VALVE ST. Refer to DISASSEMBLY