Power-Steering Pump & EPS

Stop assuming the motor and start with the codes. Electric assistance drops out for several reasons, and a weak twelve volt battery or a poor earth is far more common and far cheaper than a failed motor, because the system needs substantial current to assist and will shut down rather than brown out the network. Have the steering control unit read for stored faults and check supply voltage under load. The car remains steerable without assistance, though it takes real effort at parking speeds.

It depends on the design, which is why the catalogue lists them separately and together. Some vehicles allow the motor, the control unit or the torque sensor to be replaced individually, and others build the whole assembly as one sealed unit. Read the listing carefully and match the OE number from your own vehicle. Where an individual component is available, it is much the cheaper route, though it usually still requires coding and a steering angle calibration afterwards.

It is the procedure that teaches the vehicle where straight ahead is. The stability control system, the lane keeping function and the assistance map all depend on knowing the exact wheel position, so after replacing a steering component, disturbing the column, or performing a wheel alignment, the sensor has to be reset with a scan tool or by a defined driving sequence. Skipping it leaves warning lamps and, worse, a stability system working from a false reference.

Check the fluid before condemning it. A whine that rises with engine speed and worsens on full lock is the classic symptom of a pump running short of fluid or drawing air, and the cause is often a perished feed hose on the suction side letting air in rather than a worn pump. Look for foaming in the reservoir, which is the giveaway. If the fluid is at the correct level and clean and the whine persists, the pump itself is worn and the assembly is the part.

Look at the pipe runs and the rack gaiters. Steering fluid leaks often evaporate off a hot surface before they reach the ground, so a slow loss shows up as a falling level with nothing on the driveway. Trace the feed and return lines for damp patches and check the unions, then look inside the rack gaiters for fluid, which indicates a failed rack seal rather than a pipe. Formed feed and return line assemblies are listed here by position.

On the high pressure side, no. Feed lines operate at pressures well above what generic hose and fittings tolerate, they are formed to follow a specific route away from heat and moving parts, and the crimped ends are made for that assembly. A homemade line that bursts on full lock removes assistance instantly at the worst moment. Return lines are lower pressure and more forgiving, and the formed part is still the sensible purchase because routing matters. Order by position and OE number.

Brackets, sleeves, sliders and hoses sit at the bottom of the range. Formed feed and return line assemblies and reservoirs are modest. Hydraulic pump assemblies cost more, and EPS motor and controller units sit at the top of the category since they combine a motor, electronics and calibration data. The live minimum and maximum are shown in the band at the top of this page. Read the codes before ordering an electric component, because the price difference against a battery or an earth repair is large.

The car steers, and it takes considerably more effort, particularly at parking speeds and on full lock. Nothing is disconnected mechanically when assistance fails, since there is always a mechanical path from wheel to rack. The practical risks are underestimating the effort needed in an emergency manoeuvre and the possibility that whatever caused the failure also affects lane keeping or stability functions. Treat it as a repair to make promptly rather than an emergency stop by the roadside.

Exactly what the manufacturer specifies, which varies between dedicated power steering fluids and particular automatic transmission fluids depending on the design. Mixing types damages seals and can make the assistance behave differently when hot. Check the reservoir cap and the handbook, use a freshly opened container, and bleed the system properly afterwards by turning lock to lock with the front wheels raised. Fluids are listed in their own category on the site.

On nearly every current vehicle, yes. A replacement unit arrives without the vehicle's configuration and without a learned zero position, so it needs coding to the platform and a steering angle calibration before the assistance map and the stability system will work correctly. Some vehicles also require a short calibration drive. Confirm that your workshop has the diagnostic access before the part is ordered, since an uncoded unit leaves the vehicle with warning lamps and no assistance.

Only where the OE number agrees. Assistance maps are tuned to vehicle weight, tyre size and geometry, so a unit from a heavier or lighter version of the same body will assist incorrectly even if it bolts on and codes. Hydraulic pumps differ in flow rate and pressure relief settings, which is equally invisible. Read the number from your own part, match it, and where the reference brings back nothing, send it through the quote form so the factory catalogue is checked properly.

Yes. Electric steering control units and motors are ordered against the number and often need configuration afterwards, which is why they are handled by enquiry rather than shown with a price. Hydraulic pumps and lines on the older applications are the other common case. Send the reference and say whether your car uses a column mounted motor or a rack mounted one, since the two are entirely different assemblies. If the steering went heavy with a warning lamp, have the torque sensor and the supply voltage checked first. A weak twelve volt supply makes assistance drop out and mimics a failed motor.