Five most common EPS failures
1. Ford Focus MKIII, C-MAX MKII, Kuga MKI, Transit Connect (2011-2017)
The basic hardware used is the same throughout the Ford family of electric steering racks, with different software providing each vehicle’s characteristics. In this design, a motor is attached directly to the rack that drives a linear recirculating ball wormdrive via an internal belt. Unfortunately, the control unit that is built into the motor assembly on the nearside of the steering rack suffers from both hardware and software failures. The control unit stops communicating with the car’s body control module – look for the common fault code of ‘U3000 -49/53’. It is thought that software updates alone give only a short-term fix.
2. Vauxhall Meriva Mk1
Bizarrely, the original Meriva used a column-mounted EPS that was not shared with other Vauxhall models. Should the PAS fail completely (and/or the EPS warning lamp illuminates), the assistance level will vary, depending on direction, or if the steering groans/vibrates. The steering torque sensor is the most common cause. Look for code ‘C1500’. While the sensor can be renewed separately, the control unit will require calibrating. Alternatively, intermittent failure that is accompanied by code ‘C1002’ indicates complete motor control unit failure, requiring a replacement column.
3. Fiat Panda (2004-2014), 500 and Grande Punto (to 2014)
EPS issues continued with Fiat cars long after the Punto ended production. The Panda and 500 models suffer also from high failure rates of their columns, although the Panda column is unique. Like the Vauxhall Meriva, the steering torque sensor is the main cause of failure (generating code ‘C1002’) and the symptoms are the same as those described earlier. You can replace the Panda’s sensor separately. However, the code ‘C1001’ indicates motor control unit failure and replacing the column will be required. Like that of our Punto demonstration, a correctlyremanufactured column should not require any further programming. Unlike those of the Panda and Punto, the Grande Punto’s Delphi EPS column is of a different design, where the column, motor and ECU are integral. Should there be any issues, the entire column will have to be replaced. While not interchangeable, the same problem strikes the columns fitted to the basic 500 model.
4. Volkswagen Golf MKV and MKVI, Audi A3 (to 2013)
Three different types of EPS racks were fitted to these vehicless. The first types lasted until 2005, Zf-manufactured racks were fitted from 2005-2009 and the last generation ran from 2009-2013. In general, the newer ones are the most reliable. Failures arise due to water ingress into the rack from poorly-fitted, or split gaiters. Failure of the top pinion seal can allow water and dirt to seep into the rack’s mechanism. Torque sensor failure within the rack is a known issue, as are malfunctions of the motor/control unit.
5. Vauxhall Corsa D
Look for intermittent faults and not just total failure. Codes ‘C0460 (steering angle sensor)’ or ‘C0545 (steering torque sensor)’ mean that the column will need replacing. Motor problems start intermittently, but end up being permanent. The integral control circuit board inside the motor is known to burn out. Failure of the chips within the EPS ECU can leave false diagnostic codes, leading you to suspect the motor when the ECU is to blame. A new, or remanufactured, ECU must be matched and calibrated diagnostically with the torque sensor. The steering angle sensor is also a known weakness, resulting in the steering becoming lighter in one direction than the other. It can also cause the ECU to shut down. As these columns seem to be intrinsically fragile and difficult to calibrate, it is recommended that the complete column is changed, even though certain individual components can be replaced.