Fault code P1689 – a step-by-step guide to diagnosing and fixing it

Error code P1689 is displayed and the check engine light is on - what does this mean?

The DTC P1689 is a manufacturer-specific fault code that is recognized by the OBD system and mainly relates to the fuel pump relay circuit. This trouble code mainly occurs in Chrysler, Dodge and Jeep vehicles and indicates a problem with the electrical supply to the fuel pump.

What can cause this fault code?

• Defective fuel pump relay
• Damaged fuel pump fuse
• Broken cable connections in the fuel system
• Corroded or loose plug connections
• Defective fuel pump
• Faulty wiring to the PCM (Powertrain Control Module)
• Damaged engine control unit
• Problems with the vehicle ground

What symptoms occur in parallel with fault code P1689?

• Starting problems: The vehicle is difficult or impossible to start, especially after long periods of inactivity.
• Engine misfires: The engine runs unevenly or stops while driving.
• Loss of power: Noticeable reduction in engine power, especially when accelerating.
• Jerky idling: The engine runs unstable or stalls when idling.
• Smell of fuel: Smell of gasoline in or around the vehicle.

How to fix the problem of fault code P1689?

• Repairing fault code P1689 requires a systematic approach to identify the exact cause.
• Replace the fuel pump relay: Locate the fuel pump relay in the fuse box and replace it with a new, compatible relay
• Check and replace fuses: Check all fuel-related fuses with a multimeter and replace blown fuses
• Repair electrical connections: Inspect all cable connections to the fuel pump, clean corroded contacts and repair damaged cables
• Replace fuel pump: If the pump is faulty, lower the fuel tank, remove the old pump and install a new fuel pump
• PCM diagnosis and replacement: Have the engine control unit diagnosed by a specialist and programmed or replaced if necessary
• Check ground connections: Clean and tighten all fuel system ground connections and replace if corroded