Inspection and Verification
Inspection and VerificationWARNING: If equipped with fire suppression system, refer to Fire Suppression System for Important Safety Warnings.
CAUTION: Do not hold the steering wheel at the stops for an extended amount of time. Damage to the power steering pump can result.
NOTE: Make the following preliminary checks before repairing the steering system:
1. Verify the customer concern.
2. Visually inspect for obvious signs of mechanical or electrical damage.
Visual Inspection Chart:
3. NOTE: The 3 areas that should be inspected for possible contamination are the power steering reservoir filter, flow control and pressure relief valve in the pump, and the check valve in the inlet port on the power steering gear (if equipped).
Inspect the power steering fluid for the following conditions:
^ Aerated or foamy: Purge the power steering system.
^ Overheating or contamination: Flush the power steering system.
4. NOTE: It may be necessary to add power steering fluid to achieve the correct level.
Check the power steering system for fluid leaks. With the ignition OFF:
^ check the power steering fluid level.
^ wipe off the power steering pump, power steering pressure hose, power steering return hose, power steering fluid cooler, hose assembly and steering gear.
^ CAUTION: Do not hold the steering wheel at the stops for an extended amount of time. Damage to the power steering pump can occur.
Start the engine and turn the steering wheel from stop-to-stop several times and check for leaks.
^ If a fluid leak from the steering line-to-steering gear clamp plate is evident, refer to Power Steering.
5. Inspect the power steering pressure and return hoses, fittings and O-rings for leaks.
^ If a leak is detected at a power steering pressure or return hose, install a new hose.
^ If a leak is detected between a fitting nut, seal the fitting nut using a new Teflon joint seal.
^ If a leak is detected at a fitting or clamp plate, tighten to specification. If leak is still evident, visually inspect the fittings, clamp plate, O-rings and Teflon seals. Install new components as necessary.
^ If a leak is detected at the power steering reservoir, install a new reservoir.
^ If a leak is detected at a constant tension spring clamp, verify that the hose is fully installed on the fitting and that the hose clamp is correctly positioned. If the leak remains, install a new constant tension spring clamp.
^ If a leak is detected at a screw clamp joint, tighten the screw clamp. If the leak remains, inspect the tube end and install a new hose.
^ If a leak is detected at the power steering pump, install a new power steering pump.
NOTE: To inspect for leaks it may be necessary to remove the squeeze-type clamp from the steering gear boots.
6. Inspect the power steering gear for leaks. If a leak is detected at the power steering gear, install a new power steering gear.
External Leak Check - Potential Power Rack-and-Pinion Steering Gear Leak Points:
7. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
8. NOTE: Make sure to use the latest scan tool software release.
If the cause is not visually evident, connect the scan tool to the data link connector (DLC).
9. NOTE: The vehicle communication module (VCM) LED prove out confirms power and ground from the DLC are provided to the VCM.
If the scan tool does not communicate with the VCM:
^ check the VCM connection to the vehicle.
^ check the scan tool connection to the VCM.
^ refer to Information Bus (Module Communications Network), No power to the scan tool, to diagnose no communication with the scan tool.
10. If the scan tool does not communicate with the vehicle:
^ verify the ignition key is in the ON position.
^ verify the scan tool operation with a known good vehicle.
^ refer to Information Bus (Module Communications Network) to diagnose no response from the powertrain control module (PCM).
11. Carry out the network test.
^ If the scan tool responds with no communication for one or more modules, refer to Information Bus (Module Communications Network).
^ If the network test passes, retrieve and record continuous memory diagnostic trouble codes (DTCs).
12. Clear the continuous DTCs and carry out the self-test diagnostics for the air suspension/variable assist power steering (VAPS) module.
13. If the DTCs retrieved are related to the concern, go to Air Suspension/Variable Assist Power Steering (VAPS) Module Diagnostic Trouble Code (DTC) Index. Diagnostic Trouble Code Tests and Associated Procedures For all other DTCs, refer to Body Control Systems (Multifunction Electronic Control Module).
14. If no DTCs related to the concern are retrieved, GO to Symptom Chart-Noise/Vibration. Symptom Related Diagnostic Procedures