The P2535: Ignition Switch Run/Start Position Circuit High code indicates that there is a high voltage or signal issue in the ignition switch run/start position circuit. This can be caused by a malfunctioning ignition switch, a short circuit, or wiring issues that lead to an excessive voltage supply. High voltage in this circuit can cause the ignition system and other electrical systems to operate incorrectly.
P2535 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P2535: Ignition Switch Run/Start Position Circuit High |
| Is it serious? | Moderately serious. Excessive voltage can cause erratic behavior of vehicle systems, potentially leading to starting issues or damage to electrical components. |
| Possible causes | – High voltage or signal in the ignition switch run/start position circuit – Faulty ignition switch – Wiring or connector issues |
| How to diagnose? | – Measure the voltage in the ignition switch run/start position circuit – Inspect and test the ignition switch – Check wiring and connectors – Replace faulty components if needed |
Code Meaning
The P2535: Ignition Switch Run/Start Position Circuit High code indicates that the voltage detected in the ignition switch circuit is higher than expected when the switch is in the run or start position. This could be due to a short to power, a fault in the ignition switch, or wiring and connector issues. High voltage can cause malfunctions in the ignition and other critical systems, affecting drivability and overall vehicle performance.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to determine if there are additional related codes that may provide more information about other issues affecting the ignition system. | OBD-II Scanner |
| Measure Voltage in the Ignition Switch Run/Start Position Circuit | Use a multimeter to measure the voltage in the ignition switch run/start position circuit. Compare the readings with the manufacturer’s specifications. If the voltage is above the normal range, further investigation is needed. | Multimeter |
| Inspect the Ignition Switch | Visually inspect the ignition switch for signs of wear or damage. Ensure that it operates smoothly in all key positions and check for loose or corroded contacts that could be causing excessive voltage readings. | Flashlight, Safety Gloves |
| Check Wiring and Connectors | Examine the wiring and connectors in the ignition circuit for signs of short circuits, damaged insulation, or corroded connections. Short circuits to power can lead to high voltage in the circuit. Repair or replace any faulty wiring and connectors. | Flashlight, Multimeter |
| Test the Ignition Switch for Proper Function | Use a multimeter to test the output of the ignition switch in the run and start positions. The voltage output should be within the specified range. Replace the switch if the voltage remains high or fluctuates improperly. | Multimeter |
| Inspect for Short Circuits to Power | Carefully inspect the wiring for possible short circuits to a power source. A short to power could be the reason for the higher-than-expected voltage in the ignition circuit. | Multimeter |
| Verify Voltage Supply and Ground | Ensure that the ignition switch is receiving the correct voltage supply and has a reliable ground connection. An improper power supply or bad ground can lead to abnormal voltage levels in the circuit. | Multimeter |
| Inspect Fuse Box and Relays | Check the related fuses and relays for the ignition switch circuit. Verify that all fuses are intact and relays are functioning properly. Replace any that are found to be faulty to ensure the integrity of the circuit. | Fuse Puller, Multimeter |
| Replace Faulty Components | Replace any faulty components identified during the diagnostic process, such as the ignition switch, wiring, or connectors. Ensure all replacements are OEM-compatible for proper function and safety. | Replacement Parts, Vehicle Owner’s Manual |
| Clear the Code and Test the System | After replacing faulty components, clear the P2535 code using an OBD-II scanner. Start the vehicle and monitor the behavior of the ignition system in the run and start positions to confirm that voltage levels are within the correct range. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Re-scan the vehicle to ensure that the P2535 code has not returned. If the code persists, further diagnostics may be necessary to determine other underlying faults. | OBD-II Scanner |
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