No Communication Between ECM and Injection Pump Module (Dodge)
What does P1689 mean?
The P1689 code means the vehicle's onboard diagnostic system has detected: No Communication Between ECM and Injection Pump Module (Dodge). This is a critical severity code.
Common Symptoms
- Engine will not start
- Check Engine Light on
- No fuel injection pulse
- Loss of communication error on scan tool
- Engine cranks normally but will not fire
Probable Causes (Ranked by Likelihood)
- Failed VP44 injection pump controller Very High
- Broken wiring between ECM and injection pump High
- Corroded communication bus connector Moderate
- ECM internal communication failure Low
Step-by-Step Diagnostic Procedure
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Attempt to communicate with the injection pump module using a Cummins-compatible scan tool.
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Check the wiring harness between the ECM and injection pump for damage, especially near the engine.
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Inspect the injection pump connector for corrosion, heat damage, or loose pins.
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Verify the ECM has proper power, ground, and communication bus voltage.
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If the wiring is intact but communication fails, the VP44 pump controller has likely failed.
Frequently Asked Questions
Is this the same as a dead VP44 pump?
Often yes. When the VP44 controller dies, it stops communicating with the ECM. However, wiring issues can also cause this code, so diagnose before replacing.
How much does a VP44 pump cost?
A remanufactured VP44 typically costs $800-$1500 for the pump alone. Installation adds $500-$800 in labor.
Can I prevent VP44 failure?
Yes. Install a quality lift pump, change fuel filters regularly, and ensure clean fuel. Low fuel pressure is the primary cause of VP44 failures.