DEFINITION: The Power Steering System Testing 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. |
The numbers below refer to the step numbers on the diagnostic table.
This step tests the system for restrictions.
This step tests the following components for the following conditions:
• | The pump for internal leakage |
• | The power steering pipes for restrictions |
This step tests the ability of the pump to regulate flow at minimum pressure.
This step tests the ability of the pump to regulate flow under normal operating conditions.
This step tests the internal components of the pump and the gear.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Inspect the power steering fluid for the following indications of contamination:
Is the fluid contaminated? | -- | Go to Step 2 | Go to Step 3 | ||||||
2 | Flush the power steering system. Refer to Power Steering System Flushing. Did you complete the procedure? | -- | Go to Step 3 | -- | ||||||
3 |
Important: In order to accurately diagnose the system, the condition must be present during the test procedure. Attempt to duplicate the condition. Is the condition present? | -- | Go to Step 4 | System OK | ||||||
4 |
Notice: Refer to Steering Wheel in the Full Turn Position Notice in the Preface section. Did you complete the installation? | -- | Go to Step 5 | -- | ||||||
5 |
Important: The steering must not be against the steering stop. Is the pressure reading greater than the specified value? | 1379 kPa (200 psi) | Go to Step 6 | Go to Step 7 | ||||||
6 |
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 15 | -- | ||||||
7 |
Is the decrease in flow greater than 3.8 L (1 gal) per minute? | 4827 kPa (700 psi) | Go to Step 11 | Go to Step 8 | ||||||
8 |
Important: Do not leave the valve closed for more than 5 seconds, or internal pump damage could occur. Fully close then open the J 44721 valve 3 times. Record all of the high pressure readings. Refer to Power Steering Pump Specifications, for power steering system pressure relief specifications. Are the three high pressure readings within specifications? | -- | Go to Step 9 | Go to Step 13 | ||||||
9 | Are the three high pressure readings within 245 kPa (50 psi) of each other? | -- | Go to Step 10 | Go to Step 13 | ||||||
10 |
Is the flow reading within specifications? | -- | Go to Step 11 | Go to Step 13 | ||||||
11 | Is the difference between the flow reading recorded in step 7.2 and the minimum flow specification more than 3.8 L (1 gal) per minute? | -- | Go to Step 13 | Go to Step 12 | ||||||
12 |
Notice: Refer to Steering Wheel in the Full Turn Position Notice in the Preface section. Turn the steering wheel from steering stop to steering stop and record the flow readings at each stop. Is the flow lower than 3.8 L (1 gal) per minute? | -- | Go to Step 15 | Go to Step 14 | ||||||
13 | Replace the power steering pump. Refer to Power Steering Pump Replacement. Did you complete the replacement? | -- | Go to Step 15 | -- | ||||||
14 | The power steering gear is leaking across the piston or bypassing the valve circuit. Replace the power steering gear. Refer to Steering Gear Replacement in Power Steering System. Refer to Steering Gear Replacement in Power Steering System. Did you complete the replacement? | -- | Go to Step 15 | -- | ||||||
15 | Test the power steering system for the original condition. Does the original condition still exist? | -- | Go to Step 5 | Go to Step 16 | ||||||
16 |
Did you complete the procedure? | -- | System OK | -- |