Hydraulic Pressure In P/S Circuit Check

After cleaning joint of high pressure hose and P/S pump thoroughly, disconnect hose from pump and install special tool (oil pressure gauge, attachment and hose).
CAUTION: Take care not to cause damage to A/C condenser during service operation, if equipped.

Special tool

(A): 09915-77410

(B): 09915-77420

Fig 1: Identifying High Pressure Hose, Fittings & Special Tools (Oil Pressure Gauge, Attachment & Hose)
Courtesy of SUZUKI OF AMERICA CORP.
Check each connection for fluid leakage and bleed air. See POWER STEERING SYSTEM AIR BLEEDING PROCEDURE .
With engine idling, turn steering wheel and warm up engine till temperature of fluid in tank rises to 50-60°C (122-140°F).

Fig 2: Checking P/S Fluid Temperature
Courtesy of SUZUKI OF AMERICA CORP.
Check back pressure by measuring hydraulic pressure with engine idling and hands off steering wheel. When back pressure is higher than specified values, check control valve and piping for clogging.
Back pressure: Lower than 1000 kPa (10 kg/cm² , 142 psi)

Fig 3: Identifying P/S Components & Fluid Flow, (When Checking Back Pressure)
Courtesy of SUZUKI OF AMERICA CORP.
Checking P/S Relief Pressure
1. Increase engine speed to about 1500 r/min. (RPM). Close gauge valve gradually while watching pressure increase indicated by gauge and take reading of relief pressure (maximum hydraulic pressure).
  If it is higher than specified values, possible cause is malfunction of relief valve.
  
  If it is lower than specified values, possible cause is either failure of P/S pump or setting of relief valve spring.
  
  Relief pressure when gauge valve is closed (G16 Engine): 6200-7000 kPa (62-70 kg/cm² , 882-995 psi)
  
  Relief pressure when gauge valve is closed (J20 Engine): 6700-7500 kPa (67-75 kg/cm² , 953-1067 psi)
  
  Relief pressure when gauge valve is closed (H25 Engine): 7050-7850 kPa (70.5-78.5 kg/cm² , 1003-1116 psi)
  
  CAUTION: Be sure not to close gauge valve for longer than 10 seconds.
  
  Fig 4: Identifying P/S Components & Fluid Flow, (With Gauge Valve Closed)
  Courtesy of SUZUKI OF AMERICA CORP.
2. Open gauge valve fully and increase engine speed to about 1500 r/min. (RPM). Then turn steering wheel to the left or right fully and take reading of relief pressure.
  If it is higher than specified values, possible cause is malfunction of relief valve.
  
  If it is lower than specified values, possible cause is failure in steering gear box. Replace gear box.
  
  Relief pressure when gauge valve is closed (G16 Engine): 6200-7000 kPa (62-70 kg/cm² , 882-995 psi)
  
  Relief pressure when gauge valve is closed (J20 Engine): 6700-7500 kPa (67-75 kg/cm² , 953-1067 psi)
  
  Relief pressure when gauge valve is closed (H25 Engine): 7050-7850 kPa (70.5-78.5 kg/cm² , 1003-1116 psi)

CAUTION: Be sure not to hold steering wheel at fully turned position for longer than 10 seconds.

Fig 5: Identifying P/S Components & Fluid Flow, (With Gauge Valve Fully Open)

Courtesy of SUZUKI OF AMERICA CORP.