diff --git a/charger/eebus.go b/charger/eebus.go
index 19d9d8fb4..b088d1800 100644
--- a/charger/eebus.go
+++ b/charger/eebus.go
@@ -581,11 +581,11 @@ func (c *EEBus) Identify() (string, error) {
 
 var _ api.Battery = (*EEBus)(nil)
 
-// Soc implements the api.Vehicle interface
+// Soc implements the api.Battery interface
 func (c *EEBus) Soc() (float64, error) {
 	evEntity, ok := c.isEvConnected()
 	if !ok {
-		return 0, nil
+		return 0, api.ErrNotAvailable
 	}
 
 	if !c.uc.EvSoc.IsScenarioAvailableAtEntity(evEntity, 1) {