Lost Communication with Fuel Pump Control Module
2012-2019 Fiat 500 1.4L I4
Description
Cannot communicate with the fuel pump control module that manages fuel pump speed and pressure.
Symptoms
- Engine stalling
- No start condition
- Low fuel pressure codes
- Fuel pump not running
- Extended crank time
Common Causes
- Fuel pump module failure
- CAN bus wiring damage
- Module power loss
- Fuse blown
- Fuel pump connector issue
Diagnostic Steps
- Check fuel pump module fuse
- Test module power and ground
- Check CAN wiring
- Test fuel pump operation directly
- Check fuel pump relay
Repair Notes
Check fuel pump relay and fuse first. Module mounted near fuel tank is prone to corrosion.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0006High Speed CAN Communication Bus (-) Open
- U0007High Speed CAN Communication Bus (-) Low
- U0008High Speed CAN Communication Bus (-) High
- U0009High Speed CAN Communication Bus Shorted Together
- U0010Medium Speed CAN Communication Bus
U0109 on Other Vehicles
Fiat 124 Spider
2017-2020 1.4L I4 Turbo
Fiat 500 Abarth
2012-2019 1.4L I4 Turbo
Fiat 500 BR
2011-2020 1.4L I4 Flex Fire Evo
Fiat 500 PL
2007-2025 1.0L I3 Hybrid FireFly 70
Fiat 500 PL
2007-2025 1.2L I4 Fire 69
Fiat 500L
2014-2020 1.4L I4 Turbo
Fiat 500X
2016-2024 1.4L I4 Turbo
Fiat Argo
2017-2025 1.0L I4 Flex Firefly
Common Questions
What does code U0109 mean on a 2012-2019 Fiat 500?
U0109 stands for "Lost Communication with Fuel Pump Control Module". Cannot communicate with the fuel pump control module that manages fuel pump speed and pressure.
What are the symptoms of U0109 on a Fiat 500?
Common symptoms of U0109 include: Engine stalling, No start condition, Low fuel pressure codes, Fuel pump not running, Extended crank time.
What causes U0109 on a 2012-2019 Fiat 500?
Common causes of U0109 include: Fuel pump module failure, CAN bus wiring damage, Module power loss, Fuse blown, Fuel pump connector issue.