What it means
The ignition switch accessory-position circuit has a detected electrical fault. The code does not establish the cause or resulting accessory behavior.
At a glance
- Usually lights the check-engine light
How it works
The ignition switch provides an accessory-position signal to a receiving module, which uses it to control or report accessory power. P2536 means the accessory circuit has an electrical fault, but the code does not say whether the signal is missing, shorted, or otherwise incorrect.
Common causes
Most likely first.
- Worn or faulty ignition switch contacts
- Open or shorted accessory-position wiring
- Loose, corroded, or damaged connector
- Fault in the module receiving the switch signal
Symptoms
- Check-engine or electrical-system warning light
- Radio or other accessory power may be unavailable
- Accessories may remain powered after the key is removed
How to diagnose it
- Save freeze-frame data and note whether accessory power was unavailable or remained on when the code appeared.
- Use scan-tool data, if available, to compare the reported accessory state with the key position and actual accessory behavior.
- Inspect the ignition-switch accessory connector and wiring for loose or corroded pins, opens, shorts, and chafing.
- Check accessory-circuit continuity and test for shorts according to the wiring diagram and manufacturer's specification.
- If the circuit checks out, test the ignition-switch accessory contact and the receiving module input and connector.
Common fixes
- Clean and secure a loose or corroded accessory-circuit connector.
- Repair an open, shorted, or chafed accessory-position wire.
- Replace the ignition switch if its accessory contact fails testing.
- Repair the receiving module connector or circuit, or replace the module only after verifying the switch signal and wiring.
Can I keep driving?
The engine may still run, but lost accessories can affect visibility or communications, and accessories left on can drain the battery. Check that essential equipment works and that powered accessories switch off before leaving the vehicle.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.