P05C7
Economy Mode Switch Circuit Open
The economy-mode (ECO) switch input has an open circuit. The ECU cannot read whether the driver requested fuel-saving mode (changes throttle map, transmission shift points, climate strategy).
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: easy
Common causes
Ordered by how often each turns out to be the cause.
- Open in switch or harnessCommon
- Pin pushed back out of connector bodyLess likely
- Cracked solder joint inside the module or sensorLess likely
Parts involved
- Economy Mode Switch
P05C7 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.