P2506Charging System

ECM/PCM Power Input Signal Range/Performance

The control module has detected that its power input signal is out of the expected range or performing incorrectly. This points to unstable voltage on the module power feed, often from a relay, connection, or charging system issue.

🚗 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

#1Corroded or loose power connection$40-$200

30%

A poor connection causes voltage to vary at the module.

#2Faulty main relay$40-$150

25%

The relay supplies erratic voltage to the module.

#3Charging system fault$80-$700

25%

An over or undercharging alternator upsets module supply.

#4Wiring or ground fault$80-$300

20%

High resistance in the power or ground circuit.

🩺 Common Symptoms

Check engine light is on
Intermittent stalling
Hard starting
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 P2506

1Measure the module power feed under load and compare to battery voltage.

2Inspect and clean power and ground connections at the module.

3Test the main relay and the charging system output.

4Repair the faulty component, then clear and retest.

❓ Frequently Asked Questions

What does range/performance mean here?

The module power voltage is not steady within the expected window, often from a loose connection or weak relay.

Can it cause stalling?

Yes. Unstable module power can cause stalling and hard starting.

Where do I start?

Check the power and ground connections at the module and test the main relay.

🔗 Related Codes

P2505P2507P2510P0562P0563