Hydraulic System Pressure Test

NOTE: Before testing, fluid temperature should be at least 176°F (80°C).

Disconnect pressure lines from steering gear and pump. Following manufacturer's instructions, install Pressure Gauge (09631-22020). See Fig 1.

Fig 1: Installing Pressure Gauge
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Bleed air from system. See HYDRAULIC SYSTEM BLEEDING under LUBRICATION . Ensure fluid level is correct. Start and idle engine. Close valve and note pressure. Open valve.
CAUTION: DO NOT keep valve closed longer than 10 seconds.

Compare pump pressure reading to specification. Refer to the POWER STEERING PUMP PRESSURE TEST SPECIFICATIONS table. Replace power steering pump if pressure is less than specified.

POWER STEERING PUMP PRESSURE TEST SPECIFICATIONS

Application	psi (kg/cm² )
2.4L (22R-E)	1070 (75)
2.7L (3RZ-FE)	1138 (80)
3.0L (3VZ-E)	1140 (80)
3.4L (5VZ-FE)	1209 (85)
4.5L (1FZ-FE)	1351 (95)

With valve open, record pressure with engine speed at 1000 and 3000 RPM. Difference between readings should not exceed 71 psi (5.0 kg/cm² ). Replace flow control valve in power steering pump if difference exceeds specification.
On Pickup with electronic power steering, turn steering wheel to full lock position. Disconnect solenoid valve electrical connector, located on steering gear. See Fig 2.

Fig 2: Testing Solenoid Valve (Pickup With Electronic Power Steering)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
With valve open and engine speed at 1000 RPM, note pressure. See POWER STEERING PUMP PRESSURE TEST SPECIFICATIONS table. If pressure is less than specified, steering gear has internal leak and must be repaired.
Connect battery voltage to solenoid valve electrical connector. See Fig 2. Note pressure reading. Maximum pressure should be 40 psi (570 kg/cm² ).
CAUTION: DO NOT connect voltage to solenoid valve longer than 30 seconds. Allow solenoid valve to cool between test procedures.
If pressure is high, use ohmmeter to measure resistance between solenoid valve connector terminals. Resistance should be 6-11 ohms. If resistance is not as specified, replace solenoid valve. If resistance is okay, remove solenoid valve from steering gear housing.
Using jumper wires, connect battery voltage and ground to solenoid valve connector terminals. Solenoid valve needle should be drawn into solenoid valve approximately 0.8" (20 mm). If solenoid valve needle does not operate as specified, replace solenoid valve.
Reconnect wiring harness to solenoid valve. Note pressure. See POWER STEERING PUMP PRESSURE TEST SPECIFICATIONS table. If pressure is less than specified, check electronic power steering system. See STEERING SYSTEM - ELECTRONIC POWER STEERING article.