2011 INFINITI QX56 low oil pressure

SCS-20
< BASIC INSPECTION >[HBMC]
CHECK INTERNAL LEAKAGE
CHECK INTERNAL LEAKAGE
Work ProcedureINFOID:0000000006256012
CAUTION:
 Clean surrounding areas of
oil injection jack using steam before starting operation, since there may
be mud on it.
 Clean oil pressure gauge (special service tool: KV40108000) jack with steam before use.
1. Remove protector of PPMU.
2. Remove cap of oil injection jack.
3. Install an oil pressure gauge (SST: KV40108000) (A) to oil injec- tion jack.
CAUTION:
 Jack must be securely inserted until a click sound can beheard.
 Pressure reducing valve (B) of the oil pressure gauge
must be closed.
4. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations. CAUTION:
Never loosen the needle valve more than required.
5. Lift up the vehicle. CAUTION:
Check that tires never contact the ground.
6. Tighten needle valves C and E of PPMU.
7. Loosen lock nut of needle valve D of PPMU and then tighten needle valve D.
8. Lift down the vehicle. CAUTION:
Check that the lift is fully lowered.
9. Write down a value of the oil pressure gauge after 5 minutes.
10. Tighten needle valve A of PPMU.
11. Loosen lock nut of needle valve B of PPMU and then tighten needle valve B.
12. Loosen needle valve C of PPMU by approximately 2 rotations. CAUTION:
Never loosen the needle valve more than required.
13. Read a value of oil pressure gauge.
14. Compare difference of reading with pressure reading in step 9.
15. Tighten needle valves A, C, and E of PPMU to the specified torque.
16. Loosen needle valves B and D of PPMU by approximatel y 2 rotations and then tighten lock nut to the
specified torque.
CAUTION:
Never loosen the needle valve more than required.
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Pressure difference
0.1 MPa or more : Normal
0.1 MPa or less : Malfunction
: 8.3 N·m (0.85 kg-m, 73 in-lb)
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Revision: 2010 May2011 QX56

CHECK INTERNAL LEAKAGESCS-21
< BASIC INSPECTION > [HBMC]
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17. Loosen pressure reducing valve (A) of oil pressure gauge and lower pressure.
CAUTION:
Be careful since oil drains sw iftly from oil drain hole (B).
18. Check that reading of oil pressure gauge is 0 MPa.
19. Remove oil pressure gauge. : 20 N·m (2.0 kg-m, 15 ft-lb)
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Revision: 2010 May2011 QX56

SCS-22
< BASIC INSPECTION >[HBMC]
CHECK FOR MALFUNCTION
CHECK FOR MALFUNCTION
Work ProcedureINFOID:0000000006256013
CAUTION:
 Clean surrounding areas of
oil injection jack using steam before starting operation, since there may
be mud on it.
 Clean oil pressure gauge (special service tool: KV40108000) jack with steam before use.
1. Remove protector of PPMU.
2. Remove cap of oil injection jack.
3. Install an oil pressure gauge (SST: KV40108000) (A) to oil injec- tion jack.
CAUTION:
 Jack must be securely inserted until a click sound can beheard.
 Pressure reducing valve (B) of the oil pressure gauge
must be closed.
4. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations.
CAUTION:
Never loosen the needle valve more than required.
5. Lift up the vehicle. CAUTION:
Check that tires never contact the ground.
6. Tighten needle valves A and C of PPMU.
7. Loosen lock nuts of needle valves B and D of PPMU and then tighten needle valves B and D.
8. Write down a value of the oil pressure gauge.
9. Lift down the vehicle. CAUTION:
Check that the lift is fully lowered.
10. Read a value of oil pressure gauge.
11. Compare difference of reading with pressure reading in step 8.
12. Tighten needle valves A, C, and E of PPMU to the specified torque.
13. Loosen needle valves B and D of PPMU by approximatel y 2 rotations and then tighten lock nut to the
specified torque.
CAUTION:
Never loosen the needle valve more than required.
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Pressure change
Pressure increases : PPMU malfunction
Pressure does not change : Shock absorber malfunction
Tightening torque : 8.3 N· m (0.85 kg-m, 73 in-lb)
Tightening torque : 20 N·m (2.0 kg-m, 15 ft-lb)
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Revision: 2010 May2011 QX56

CHECK FOR MALFUNCTIONSCS-23
< BASIC INSPECTION > [HBMC]
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14. Loosen pressure reducing valve (A) of oil pressure gauge and then lower pressure.
CAUTION:
Be careful since oil drains sw iftly from oil drain hole (B).
15. Check that reading of oil pressure gauge is 0 MPa.
16. Remove oil pressure gauge.
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Revision: 2010 May2011 QX56

SCS-24
< BASIC INSPECTION >[HBMC]
CHECK SHOCK ABSORBER FOR MALFUNCTION
CHECK SHOCK ABSORBER
FOR MALFUNCTION
Work ProcedureINFOID:0000000006256014
CAUTION:
 Clean surrounding areas of oil injection jack using steam before starting operation, since there may
be mud on it.
 Clean suspension oil pump (special servi ce tool: KV40107700) jack with steam before use.
 Clean leak check plug (special service to ol: KV40108400) jack with steam before use.
 Check each shock absorber, one by one, in accordance with the following procedures.
1. Lift up the vehicle.
2. Remove protector of PPMU.
3. Remove cap of oil injection jack.
4. Install hose (A) of a suspension oil pump (SST: KV40107700) to oil injection jack.
CAUTION:
 Jack must be securely inserted until a click sound can be
heard.
 Pressure reducing valve (B) of the suspension oil pump
must be closed.
5. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations.
CAUTION:
Never loosen the needle valve more than required.
6. Set knob (A) of suspension oil pump to the direction as shown in the figure and check that reading of pressure gauge is 0 MPa.
7. Tighten needle valves A, C, and E of PPMU.
8. Disconnect upper side pipe or lower side pipe of each shock absorber.  For front shock absorber
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Revision: 2010 May2011 QX56

CHECK SHOCK ABSORBER FOR MALFUNCTIONSCS-25
< BASIC INSPECTION > [HBMC]
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- Disconnect upper side pipe (B) of front shock absorber.
 For rear shock absorber
- Disconnect lower side pipe (B ) of rear shock absorber.
9. Install a leak check plug (SST: KV40108400) (A) to the removed pipe and tighten the leak check plug to the specified torque.
CAUTION:
 O-ring must be free of scratches and damage.
 Piping must be kept free of the intrusion of dust and dirt.
10. Loosen lock nuts of needle valves B and D of PPMU and then tighten needle valves B and D.
11. Loosening position of needle valve of PPMU varies according to shock absorber that is che cked. Loosen needle valve of PPMU
by approximately 2 rotations, as per the following table.
CAUTION:
Never loosen the needle valve more than required.
12. Set knob (A) of suspension oil pump to the direction as shown in the figure.
13. Apply pressure of up to 2.4 MPa.
14. Go to step 15 when oil comes out from lower portion of shock absorber which pipe is removed from. Go to step 16 when oil
does not come out.
15. Replace shock absorber, since shock absorber has internal leakage. Refer to FSU-10, "
Removal and Installation" (front),
RSU-8, "
Removal and Installation" (rear).
A : Lower side pipe
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A : Upper side pipe
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Tightening torque : 5.0 N·m (0.51 kg-m, 44 in-lb)
Shock absorber Loosening position of needle valve
Front LH C
Rear LH C
Front RH A
Rear RH A
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Revision: 2010 May2011 QX56

SCS-26
< BASIC INSPECTION >[HBMC]
CHECK SHOCK ABSORBER FOR MALFUNCTION
16. Shock absorber that is checked
is normal. Set knob (A) of sus-
pension oil pump to the direction as shown in the figure and
check that reading of pressure gauge is 0 MPa.
17. Tighten the loosened needle valve of PPMU.
18. Remove leak check plug from pipe. Install pipe to lower portion of shock absorber and tighten pipe to the specified torque.
CAUTION:
 O-ring must be free of scratches and damage.
 Piping must be kept free of th e intrusion of dust and dirt.
19. Check other shock absorbers in accor dance with procedures of steps 8 to 18.
20. Tighten needle valves A, C, and E of PPMU to t he specified torque, after completion of check.
21. Loosen needle valves B and D of PPMU by approximat ely 2 rotations and then tighten lock nuts to the
specified torque.
CAUTION:
Never loosen the needle valve more than required. Tightening torque : 5.0 N·
m (0.51 kg-m, 44 in-lb)
Tightening torque : 8.3 N· m (0.85 kg-m, 73 in-lb)
Tightening torque : 20 N·m (2.0 kg-m, 15 ft-lb)
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Revision: 2010 May2011 QX56

CHECK ORIFICE FOR CLOGGINGSCS-27
< BASIC INSPECTION > [HBMC]
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CHECK ORIFICE FOR CLOGGING
Work ProcedureINFOID:0000000006256015
CAUTION:
 Clean surrounding areas of oil inj ection jack using steam before starting operation, since there may
be mud on it.
 Clean oil pressure gauge (special service tool: KV40108000) jack with steam before use.
1. Remove protector of PPMU.
2. Remove cap of oil injection jack.
3. Install an oil pressure gauge (SST: KV40108000) (A) to oil injec- tion jack.
CAUTION:
 Jack must be securely inserted until a click sound can beheard.
 Pressure reducing valve (B) of the oil pressure gauge
must be closed.
4. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations.
CAUTION:
Never loosen the needle valve more than required.
5. Lift up the vehicle. CAUTION:
Check that tires never contact the ground.
6. Tighten needle valves A, C, and E of PPMU.
7. Lift down the vehicle. CAUTION:
Check that the lift is fully lowered.
8. Loosen pressure reducing valve (A) of oil pressure gauge and then lower pressure.
CAUTION:
Be careful since oil drains sw iftly from oil drain hole (B).
9. Check that reading of oil pressure gauge is 0 MPa. Close pres- sure reducing valve.
10. Loosen needle valve E of PPMU by approximately 2 rotations. CAUTION:
Never loosen the needle valve more than required.
11. Write down a value of the oil pressure gauge.
12. Tighten needle valve E of PPMU.
13. Loosen pressure reducing valve of oil pressure gauge and then lower pressure. CAUTION:
Be careful since oil drains swiftly from oil drain hole.
14. Check that reading of oil pressure gauge is 0 MPa. Close pressure reducing valve.
15. Loosen needle valve A of PPMU by approximately 2 rotations. CAUTION:
Never loosen the needle valve more than required.
16. Read a value of the oil pressure gauge after 5 minutes.
17. Compare difference of reading with pressure reading in step 11.
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Revision: 2010 May2011 QX56