Hydraulic Pump Relay
Switches the electric pump that pressurises an automated manual or dual-clutch gearbox's actuation system. Its two failure directions have opposite consequences and both are worth recognising: unable to close, there is no pump, no pressure and therefore no gear at all, so the car stops; welded closed, the pump runs whenever there is power, which overheats and destroys a motor designed for intermittent duty and flattens the battery over a few days standing. So a car that will not move and a car with a mysterious overnight drain can be the same inexpensive relay failing in opposite directions. Burnt contacts are usually a symptom rather than a cause — they point at a pump that has been cycling far more often than it should, which points in turn at a leak.
Also known as: pump relay, dsg pump relay, hydraulic relay, actuation pump relay, gearbox pump relay
Referenced by 5 codes
Codes involving this component (5)
Other components in Electrical and Charging
- Data Bus 563
- Battery 218
- Gateway Module 158
- Stability Control Module 122
- Battery Temperature Sensor 115
- Infotainment Head Unit 49
- Alternator 45
- Brake Booster Pressure Sensor 39
- A/C Refrigerant Pressure Sensor 33
- Brake Light Switch 32
- Cruise Control Switch 31
- Ignition Switch 31
- Cooling Fan Relay 28
- Starter Relay 25
- A/C Compressor 25
- Clutch Switch 24
- ECM Power Relay 21
- Roof Antenna Module 19
- Immobiliser 15
- Lighting Driver Control Module 15
- Starter Motor 14
- Transmission Control Module Power Relay 14
- Fuel Pump Relay 13
- Secondary Air Injection Relay 13
- Battery Monitoring Sensor 10
- Driver Information Centre 10
- A/C Evaporator Temperature Sensor 8
- Telematics Control Module 8
- Navigation Control Module 6
- Headlamp Levelling Actuator 6
- Head-Up Display 2
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