Ignition Switch Run/Start Position Circuit High
The P2535 code indicates that the powertrain control module (PCM) has detected a higher than expected voltage signal from the ignition switch's run/start position circuit. This circuit is responsible for signaling the PCM when the ignition key is in the run or start position. A high voltage reading suggests a short to power, a faulty ignition switch, or a wiring issue. This can affect engine starting, fuel delivery, and other systems that rely on the ignition signal.
01. Most Common Causes
- Faulty ignition switch
- Short to voltage in the ignition switch circuit
- Corroded or damaged wiring/connectors
- Failed PCM (rare)
02. Symptoms You Will Notice
- Engine may not start or stall
- Check Engine Light illuminated
- Intermittent starting issues
- Electrical accessories malfunctioning
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm the code and check for related codes.
Step 2: Inspect the ignition switch and its wiring for damage, corrosion, or loose connections.
Step 3: Test the ignition switch voltage output at the PCM connector with a multimeter.
Step 4: If voltage is high, isolate the circuit to find the short to power.
Step 5: Replace the ignition switch if faulty, or repair wiring as needed.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended as the vehicle may stall or fail to start unexpectedly, posing a safety risk.
How much does it cost to fix?▼
Typically between $50 and $150 for parts and labor, depending on the cause and vehicle model.