Ignition Switch
The switch behind the key barrel that tells the vehicle which state it should be in — accessory, run, or run-and-crank. A mechanical contact set carrying real current, so its contacts wear, and it fails in a way that misleads: some circuits still work while others do not, so a car with a fully lit dashboard can be unable to run. Worth suspecting on intermittent stalling and no-starts that have already had a fuel pump or a crank sensor fitted. On push-button vehicles there is no physical switch and the same states are broadcast by a module, so the codes persist while the cause changes.
Also known as: ignition barrel switch, key switch, starter switch, ignition contacts
Referenced by 31 codes
Codes involving this component (31)
- P2530 Ignition Switch Run Position Circuit High
- P2531 Ignition Switch Run Position Circuit Low High
- P2532 Ignition Switch Run Position Circuit High High
- P2533 Ignition Switch On/Start Position Circuit High
- P2534 Ignition Switch On/Start Position Circuit Low High
- P2535 Ignition Switch On/Start Position Circuit High High
- P2536 Ignition Switch Accessory Position Circuit Moderate
- P2537 Ignition Switch Accessory Position Circuit Low Moderate
- P2538 Ignition Switch Accessory Position Circuit High Moderate
- U300A Ignition Switch Moderate
- U300B Ignition Input Accessory/On/Start Moderate
- U300C Ignition Input Off/On/Start Moderate
- U300D Ignition Input On/Start Moderate
- U300E Ignition Input On Moderate
- U300F Ignition Input Accessory Moderate
- U3010 Ignition Input Start Moderate
- U3011 Ignition Input Off Moderate
- P25B7 Auxiliary Ignition Switch On/Start Position Circuit
- P25B8 Auxiliary Ignition Switch On/Start Position Circuit Low
- P25B9 Auxiliary Ignition Switch On/Start Position Circuit High
- U3022 Ignition Input Accessory/Off
- U3023 Control Module Input Power Circuit A — Ignition Input On/Start Circuit Correlation
- U3024 Control Module Input Power Circuit B — Ignition Input On/Start Circuit Correlation
- U302B Ignition Output Accessory/On/Start
- U302C Ignition Output Off/On/Start
Other components in Electrical and Charging
- Data Bus 563
- Battery 218
- Gateway Module 158
- Stability Control Module 122
- Battery Temperature Sensor 115
- Infotainment Head Unit 49
- Alternator 45
- Brake Booster Pressure Sensor 39
- A/C Refrigerant Pressure Sensor 33
- Brake Light Switch 32
- Cruise Control Switch 31
- Cooling Fan Relay 28
- Starter Relay 25
- A/C Compressor 25
- Clutch Switch 24
- ECM Power Relay 21
- Roof Antenna Module 19
- Immobiliser 15
- Lighting Driver Control Module 15
- Starter Motor 14
- Transmission Control Module Power Relay 14
- Fuel Pump Relay 13
- Secondary Air Injection Relay 13
- Battery Monitoring Sensor 10
- Driver Information Centre 10
- A/C Evaporator Temperature Sensor 8
- Telematics Control Module 8
- Navigation Control Module 6
- Headlamp Levelling Actuator 6
- Hydraulic Pump Relay 5
- Head-Up Display 2
Information, not instruction
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