P2538 low

Ignition Switch Accessory Position Circuit

The P2538 code means the vehicle's onboard diagnostic system has detected: Ignition Switch Accessory Position Circuit. This is a low severity code.

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Keep driving?: Yes, but fix soon
DIY difficulty: moderate
Estimated cost: $100 - $400 (parts and labor)

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Common Symptoms

Accessories not working in ACC position
Radio and power windows inactive with key in ACC
Check engine light on
Push button accessory mode not functioning

Probable Causes (Ranked by Likelihood)

Faulty ignition switch accessory contacts Very High
Open circuit in accessory position wiring High
Body control module not receiving ACC signal Moderate
Blown accessory circuit fuse Moderate

Step-by-Step Diagnostic Procedure

Test voltage at accessory circuit with key in ACC position
Check accessory fuse and relay
Inspect ignition switch connector for ACC circuit
Verify body control module receives ACC signal

Frequently Asked Questions

Can I still drive with P2538?

Yes. P2538 affects the accessory position only, not the run or start positions. The engine will run normally; only ACC-position functions are affected.

What works in the accessory position?

The ACC position typically powers the radio, power windows, power outlets, and other accessories without starting the engine.

Is P2538 related to push-button start issues?

On push-button vehicles, pressing the start button without your foot on the brake activates ACC mode. P2538 can indicate this mode is not being properly activated.