01 How to Tell If Your Brake Booster or Master Cylinder Is Bad • 02 Do All Four Brakes in a Car Engage When Braking? • 03 How to Fix a Car Engine That Stops Abruptly and Won't Start • 04 P0300: Random or Multiple Cylinder Misfire Detected – Cause… • 05 Toyota Shocked The World With A Car That Runs Entirely On W… • 06 Symptoms of a Bad Oxygen Sensor • 07 From Knocks to Leaks: A Comprehensive Guide to Common Car E… • 08 Cylinder Liners with Fire Ring: An Essential Component in A… • 09 Unlocking the Power of Differential Lock: Traction, Problem… • 10 The Wankel Rotary Engine: Compact, Smooth, and Powerful •

DTC codes / Volkswagen codes / P1501

P1501 · VolkswagenFuel Pump Relay Circuit Short To Ground

P1501 on a Volkswagen means the engine control module (ECM) has detected a short to ground on the fuel pump relay control circuit, so the relay cannot be energised and the fuel pump may not run. The ECM monitors the relay coil circuit and sets this code when the voltage on the control wire stays abnormally low, indicating a short to chassis ground rather than a normal relay coil.

SystemPowertrain
Code typeVolkswagen specific
SeverityMedium
Fix difficultyIntermediate
AreaVehicle speed, idle control and auxiliary inputs

Symptoms you may notice

  • Engine cranks but will not start, or starts then stalls immediately
  • No fuel pump prime sound when the ignition is switched on
  • Intermittent no-start that may temporarily resolve after jiggling wiring or fuses
  • Rough running or stalling under load if the relay makes partial contact
  • Often no symptoms besides the warning light if the short is intermittent and the pump still runs
  • Other relay-controlled circuits may act erratically if the short affects shared wiring

Common causes, most likely first

  1. Fuel pump relay coil internally shorted to ground
  2. Chafed or pinched wire in the relay control circuit contacting chassis ground
  3. Corroded or water-contaminated relay socket or fuse box terminals
  4. Failed ECM driver for the fuel pump relay circuit (less common)
  5. Aftermarket alarm or immobiliser wiring tapped into the relay control circuit
  6. Loose or damaged ground connection at the relay or fuel pump mounting point

How to diagnose and fix it

  1. Scan all modules and record freeze-frame data to confirm P1501 is current and not a stored history code
  2. Locate the fuel pump relay in the relay panel and swap it with an identical known-good relay to rule out a shorted coil
  3. Inspect the relay socket, fuse box and harness for corrosion, water ingress or chafed insulation
  4. Disconnect the ECM and relay, then measure resistance from the relay control wire to chassis ground to check for a short
  5. Wiggle-test the harness while watching live relay control data or a test lamp to catch intermittent shorts
  6. Repair any damaged wire section with proper crimped and sealed connections, then clear the code and verify the fuel pump primes
  7. If the circuit tests clean but the code returns, test the ECM driver output with a scope or substitute a known-good ECM

What a fuel pump relay short really means

  • A short to ground on the control side does not always mean the relay is bad; a chafed wire behind the relay panel is a frequent culprit on older Volkswagens.
  • Water ingress into the relay box or fuse panel can create a partial short that only sets the code in damp weather, so inspect for moisture before replacing parts.
  • Aftermarket alarms and immobilisers spliced into the fuel pump relay circuit are a common hidden cause that many technicians overlook.
  • P1501 can be stored as a history code after a low battery or jump-start, so clear it and verify it returns before condemning the relay or ECM.
  • The ECM driver itself can fail and hold the control wire low, which mimics a wiring short and is often misdiagnosed as a harness fault.

Can I keep driving with P1501?

Do not drive the vehicle if it will not start or stalls repeatedly, because a failed fuel pump relay can leave you stranded. If the car runs normally and the light is intermittent, drive only to a workshop for diagnosis and avoid long trips until the circuit is repaired.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for Volkswagen vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage