P2537 — Ignition switch accessory circuit voltage too low

The code indicates a problem with the ignition switch's accessory position circuit showing lower voltage than expected. This usually means the car's computer isn't detecting the accessory position properly, which can cause issues with electrical components like the radio or dashboard lights.

Common causes

The cause is almost always one of a few things. Here they are — P2537 rarely comes from anything outside this list:

• Faulty ignition switch
• Damaged or corroded wiring/connectors
• Loose or poor electrical connections
• Blown fuse related to ignition circuit
• Faulty body control module (rare)

Where to start

In the order a sensible mechanic would work — the cheap checks first, the expensive replacements only after:

1. Check and clean ignition switch connectors
2. Inspect and repair wiring and fuses
3. Test ignition switch operation and replace if faulty
4. Check related modules if problem persists

That is what holds for P2537 in general. From here it depends on your engine — tell me which car it is and what it does, and I will give you the steps for it: real procedures, torque figures and diagrams instead of general advice.