P2505Charging System

ECM/PCM Power Input Signal

The control module has detected a problem with its power input signal. This can indicate an issue with the main power feed to the module, often related to the ignition switch, main relay, wiring, or charging system supplying the module.

🚗 Yes, in many cases, but have it checked soon. Power supply faults to the control module can cause stalling or intermittent no-starts.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Faulty main relay$40-$150

30%

The main or PCM power relay supplies erratic voltage.

#2Corroded or loose power connection$40-$200

25%

A poor connection causes voltage drop at the module.

#3Ignition switch fault$100-$350

25%

A failing switch interrupts power to the module.

#4Wiring or ground fault$80-$300

20%

High resistance or an intermittent open in the power circuit.

🩺 Common Symptoms

Check engine light is on
Intermittent stalling
Hard starting or no-start
Erratic electrical behavior

💰 Repair Cost: DIY vs Shop

DIY Cost

$40-$350

Shop Cost

$120-$500

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P2505

1Check the module power feed and ground for voltage drop.

2Test the main relay and its control and load circuits.

3Inspect wiring and connectors at the module for corrosion.

4Repair the faulty power circuit component, then clear and retest.

❓ Frequently Asked Questions

What does this code mean?

The control module is not seeing a stable power input, often from a relay, switch, or wiring fault.

Can it cause stalling?

Yes. Interruptions in module power can cause stalling and hard starting.

Is it hard to diagnose?

It can be, since intermittent power faults require checking relays, grounds, and wiring under load.

🔗 Related Codes

P2500P2502P0562P0563P0685