U0109
Lost Communication with Fuel Pump Control Module
2002-2009 GMC Envoy 4.2L I6
High SeverityNetworkGeneric (SAE)
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
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0005High Speed CAN Communication Bus (+) High
U0109 on Other Vehicles
Common Questions
What does code U0109 mean on a 2002-2009 GMC Envoy?
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 GMC Envoy?
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 2002-2009 GMC Envoy?
Common causes of U0109 include: Fuel pump module failure, CAN bus wiring damage, Module power loss, Fuse blown, Fuel pump connector issue.