Lost Communication With Fuel Pump Control Module
What does U0173 mean?
The U0173 code means the vehicle's onboard diagnostic system has detected: Lost Communication With Fuel Pump Control Module. This is a critical severity code.
Common Symptoms
- Engine stalls or will not start
- Check Engine Light illuminated
- Long cranking before engine starts
- Engine loses power intermittently
- Fuel pressure drops below specification
Probable Causes (Ranked by Likelihood)
- Failed fuel pump control module Very High
- Damaged wiring to fuel pump module High
- Corroded connector at fuel pump assembly Moderate
- Faulty fuel pump relay Moderate
Step-by-Step Diagnostic Procedure
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Check fuel pump relay and fuse in the underhood fuse box
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Verify power and ground at the fuel pump control module
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Measure fuel pressure at the fuel rail with a gauge
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Inspect wiring from module to fuel pump assembly in the tank
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Check for CAN bus communication with the fuel pump module
Frequently Asked Questions
Can I drive with code U0173?
No, do not drive. Without proper fuel pump control the engine can stall unexpectedly, creating a dangerous situation especially at highway speeds.
What causes U0173?
Most often a failed fuel pump control module located near or on the fuel tank. Corroded connectors from road exposure are also common on trucks.
Is U0173 expensive to fix?
Repair costs range from $250 to $900. The fuel pump module on trucks often requires dropping the fuel tank which adds to labor costs.