P2535: Ignition Switch On/Start Position Circuit High
What to do
Expect a start-then-stall, or a no-start. Across all the ignition switch codes the point to hold onto is that a car obviously having power does not mean the switch is fine — it feeds separate circuits through separate contacts, and only some of them need to fail. Ask for the switch to be tested rather than assumed good, especially if a fuel pump or sensor has already been fitted without fixing it.
What this code means
The run-and-start circuit reads above its valid range — an open circuit, or a short to supply.
An open circuit is the more common and produces the start-then-stall of P2533. A short to supply leaves the module reading run-or-start permanently, which has the same consequences as the permanent run signal at P2532: an engine reluctant to shut off, or a module that never powers down and drains the battery over a few days.
Across all six of these codes the practical point is the same and worth repeating once: the ignition switch is a wearing mechanical part that fails selectively, so "the car has power" is not evidence that it is working.
Likely causes
Start here
- Open circuit in ignition switch wiring · moderate
- Faulty ignition switch · moderate
- Worn ignition switch contacts · moderate
- Corroded or loose connector · easy
Less common
- Wiring shorted to voltage · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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