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.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- moderate
- Estimated cost
- $100 - $400 (parts and labor)
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What Are the Symptoms of P2538?
- 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
What Causes P2538? (Most Likely First)
- 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
Can I Still Drive with P2538?
Yes, but fix soon. P2538 is rated low severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring the light.
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.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P2538?
-
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
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Which Vehicles Commonly Get P2538?
- 2010-2020 Toyota Camry
- 2012-2019 Honda Civic
- 2008-2018 Ford F-150
- 2011-2020 Chevrolet Silverado
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