The numbers below refer to the step numbers on the diagnostic table.
Step
| Action
| Value(s)
| Yes
| No
|
Notice: If the power steering system has been serviced, an accurate fluid level
reading cannot be obtained unless air is bled from the steering system. The
air in the fluid may cause pump cavitation noise and may cause pump damage
over a period of time.
Important: In order to accurately diagnose the system, the malfunction must be
present during the test procedure.
|
DEFINITION: The Power Steering System Test Procedure will perform the following
functions:
• | Test the operation of the hydraulic power steering system. |
• | Test the operation of the power steering pump and power steering
gear. |
• | Identify restrictions in the system. |
|
1
|
- Turn the ignition switch to the OFF position.
- Place a drain pan under the vehicle in order to catch any power
steering fluid.
- Disconnect the power steering gear inlet pipe from the power steering
gear.
- Install the J 44721
and an adapter to the power steering gear on the pressure side.
- Install the J 44721
to the power steering gear inlet pipe.
- Inspect and add ONLY approved power steering fluid as necessary
in order to ensure that the power steering fluid is at the proper level and
not contaminated. Refer to
Checking and Adding Power Steering Fluid
.
Is the fluid at the proper level and free from contamination?
| --
| Go to
Step 3
| Go to
Step 2
|
2
| Fill or drain and
refill the fluid as necessary. Refer to
Checking and Adding Power Steering Fluid
.
Is the fluid at the proper level and free from contamination?
| --
| Go to
Step 3
| --
|
3
|
- Fully open the J 44721
valve.
- Start the engine.
Notice: Do not hold the steering wheel in the full turn position
longer than 5 seconds, as damage to the steering pump may result.
- Turn the steering wheel and BRIEFLY hold the steering wheel against
the steering stop in order to release any trapped air from the system.
- Inspect and ensure that all of the power steering pipe/hose connections
are not leaking.
- Verify the fluid is free of foam or discoloration. Bleed the power
steering system and add fluid if necessary. Refer to
Power Steering System Bleeding
.
- Place the steering wheel in the straight-ahead position.
- Observe the pressure reading.
Is the pressure reading GREATER than the specified value?
| 490 kPa
(71 psi)
| Go to
Step 4
| Go to
Step 5
|
4
|
Important: A restriction may be present in the power steering system. Turn off
the engine IMMEDIATELY.
Locate and repair the restriction.
Did you complete the repair?
| --
| Go to
Step 16
| --
|
5
|
- Inspect and add ONLY approved power steering fluid as necessary
in order to ensure that the power steering fluid is at the proper level.
Refer to
Checking and Adding Power Steering Fluid
.
- Allow the engine to run until the engine reaches full operating
temperature.
- Record the pressure reading and flow reading (A).
- Partially close the J 44721
valve until the system pressure reaches the specified value,
then record the FLOW reading (B).
- Subtract flow reading B from flow reading A.
Is the flow DECREASE greater than 3.8 L (1 gal) per minute?
| 4827 kPa
(700 psi)
| Go to
Step 11
| Go to
Step 6
|
6
|
Notice: Do not leave the valve fully closed for more than 5 seconds, or the
pump could be damaged internally.
Fully close then open the J 44721
valve 3 times. Record all of the high pressure readings.
Refer to
Power Steering Pump Specifications
.
Are the three high pressure readings within specifications?
| 6374-7416 kPa
(924-1076 psi)
| Go to
Step 7
| Go to
Step 13
|
7
| Are the
three high pressure readings within 245 kPa (50 psi) of each
other?
| --
| Go to
Step 8
| Go to
Step 12
|
8
|
- Increase the engine speed to approximately 3000 RPM.
- Record the flow reading. Refer to
Power Steering Pump Specifications
.
Is the actual flow reading within specifications?
| 4.5 liters/minute (1.2 gallons/minute)
| Go to
Step 9
| Go to
Step 11
|
9
| Is the difference
between the actual flow reading and the maximum flow specification GREATER
than the specification?
| 3.8 liters/minute (1 gallon/minute)
| Go to
Step 14
| Go to
Step 10
|
10
|
Notice: Do not hold the steering wheel in the full turn position
longer than 5 seconds, as damage to the steering pump may result.
Turn the steering wheel from steering stop to steering
stop and record the FLOW readings at each stop.
Is the flow LESS than the specification?
| 3.8 liters/minute (1 gallon/minute)
| Go to
Step 17
| Go to
Step 15
|
11
| Replace the
power steering pump. Refer to
Power Steering Pump Replacement
.
Did you complete the replacement?
| --
| Go to
Step 16
| --
|
12
|
- Remove the power steering pump flow control valve. Refer to
Power Steering Pump Flow Control Valve Replacement - On Vehicle
.
- Inspect the flow control valve.
If any burrs or scratches are noticed on the flow control valve, replace
the flow control valve. Do NOT attempt to clean the flow control valve. Refer
to
Power Steering Pump Flow Control Valve Replacement - On Vehicle
.
- Inspect the flow control valve bore.
If any burrs or scratches are present in the control valve bore, replace
the power steering pump. Refer to
Power Steering Pump Replacement
.
Did you complete the repair?
| --
| Go to
Step 16
| --
|
13
| Replace the power steering pump flow control valve. Refer to
Power Steering Pump Flow Control Valve Replacement - On Vehicle
.
Did you complete the replacement?
| --
| Go to
Step 16
| --
|
14
|
- Remove the power steering pump flow control valve and inspect
for any wear or damage. Do NOT disassemble the flow control valve.
- If the flow control valve is worn damaged, replace the flow control
valve. Refer to
Power Steering Pump Flow Control Valve Replacement - On Vehicle
.
Did you complete the repair?
| --
| Go to
Step 16
| --
|
15
| The power steering gear is leaking across the piston or bypassing
the valve circuit. Replace the power steering gear. Refer to
Steering Gear Replacement
.
Did you complete the replacement?
| --
| Go to
Step 16
| --
|
16
| Test the power steering system for the original condition.
Does the original condition still exist?
| --
| Go to
Step 1
| Go to
Step 17
|
17
|
- Disconnect and remove the J 44721
from the vehicle.
- Connect the power steering gear inlet pipe to the power steering
gear.
- Bleed the power steering system and add fluid as necessary. Refer
to
Power Steering System Bleeding
.
Did you complete the repair?
| --
| System OK
| --
|