Volkswagen up! ABS fault

This ABS pump and module is fitted to the Volkswagen up! range of small family vehicles and the Seat Mii and Skoda Citigo (rebadged versions of the up!)

Common ABS function failure will have you scanning the vehicle with diagnostic tools or taking the car to a garage, you will have likely found fault codes stored in the ABS, the most common being:

C107701 – ABS Hydraulic / Return Flow Pump. We are seeing large numbers of this ABS pump and module being sent into us for testing for faults related to C107701 – ABS Hydraulic / Return Flow Pump. The symptoms of this fault code being present include no emergency ABS braking assistance  and the constant illumination of the ABS and traction control warning light.

Wheel speed sensor fault codes: predominately C101B01 – Wheel Speed Sensor Front Right Electrical Fault & C101A14 – Wheel Speed Sensor Front Left Electrical Fault.

Having these fault codes stored will trigger constant ABS and traction control warning lights and prevent effective ABS assistance. These codes, again, are commonly caused by factors outside of the ABS pump and module itself.

Solution

C107701 – ABS Hydraulic / Return Flow Pump.

This fault is not usually caused by the ABS unit itself, more often than not it is due to a supply voltage error. Checks should be made for the ABS pump fuse, this is the higher amperage fuse for the ABS located in the engine bay fuse box. The resistance of the ABS fuse should reads 0 ohms, if it measures open circuit, replace the fuse and retest the ABS. Check and change the 40amp fuse (F5) as necessary and carry out wiring checks to ensure that there are no voltage drops.

Wheel speed sensor fault codes: predominately C101B01 – Wheel Speed Sensor Front Right Electrical Fault & C101A14 – Wheel Speed Sensor Front Left Electrical Fault.

Often this fault is caused by wiring defects to/from the wheel speed sensor, or indeed, the wheel speed sensor itself. When viewing live data we would expect to see a defective or missing signal from the affected sensor.

Common Failure symptoms:

• No ABS emergency braking assistance
• ABS light illumination
• Traction control light illumination

Common fault codes:

• C1077 – ABS Hydraulic / Return Flow Pump.
• C101B01 – Wheel Speed Sensor Front Right Electrical Fault
• C101A14 – Wheel Speed Sensor Front Left Electrical Fault.

Affected Vehicles:

• Volkswagen up! (all variants: Take up!, Move up!, High up! and up! Beats) 2011 – 2019
• Seat Mii 2011 – 2019
• Skoda Citigo 2011 – 2019

Common failing part numbers:

• 1S0 614 517 C / 1S0 614 517 D / 1S0 614 517 E
• 1S0 614 517 F / 1S0 614 517 L / 1S0 614 117 J / 1S0 614 117 L