Contents: Examination ⇓ Replacement ⇓
Examination
1. The contact pressure sensor in the power steering hydraulic system is located on the hydraulic system pump. When the hydraulic pressure reaches a preset value, the sensor closes contacts and sends a signal to the electronic control unit. The control unit uses this information to maintain engine speed when maneuvering the vehicle in tight spaces. A sensor malfunction is detected by the diagnostic system and a corresponding code appears in the system memory (see paragraph 2).
2. The need to check the pressure sensor in the hydraulic steering system arises in cases where the engine stalls when parking or the idle speed is too high.
3. Check the connector pin assignments in the electrical diagrams at the end chapter 12.
4. Disconnect the wiring from the sensor and connect an ohmmeter to the sensor contacts.
5. Start the engine and let it idle.
6. Turn the front wheels to the straight-ahead position and read the ohmmeter reading. It should show infinity (chain break).
7. Turn the wheels in any direction and observe the ohmmeter. The sensor contacts should close when the steered wheels approach any of the extreme positions. When the contacts are closed, the ohmmeter will show zero.
8. If the sensor behaves differently, replace it.
Replacement
9. If the vehicle has a V-shaped engine, raise the vehicle and support it on stands.
10. Disconnect the electrical wiring from the sensor and unscrew the sensor from the pump.
11. Screw in the new sensor and tighten it securely. Connect the electrical wiring.
12. Bleed the air from the hydraulic steering system (see chapter 10). If necessary, add fluid to the system (see chapter 1).