diff --git a/vehicle/audi.go b/vehicle/audi.go
index 1cb31f3c8..8691a480f 100644
--- a/vehicle/audi.go
+++ b/vehicle/audi.go
@@ -97,7 +97,7 @@ func NewAudiFromConfig(other map[string]interface{}) (api.Vehicle, error) {
 		Helper:   request.NewHelper(log),
 		user:     cc.User,
 		password: cc.Password,
-		vin:      cc.VIN,
+		vin:      strings.ToUpper(cc.VIN),
 		brand:    "Audi",
 		country:  "DE",
 	}
diff --git a/vehicle/bmw.go b/vehicle/bmw.go
index c26b4c803..73ab2f26c 100644
--- a/vehicle/bmw.go
+++ b/vehicle/bmw.go
@@ -64,7 +64,7 @@ func NewBMWFromConfig(other map[string]interface{}) (api.Vehicle, error) {
 		Helper:   request.NewHelper(log),
 		user:     cc.User,
 		password: cc.Password,
-		vin:      cc.VIN,
+		vin:      strings.ToUpper(cc.VIN),
 	}
 
 	v.chargeStateG = provider.NewCached(v.chargeState, cc.Cache).FloatGetter()
diff --git a/vehicle/porsche.go b/vehicle/porsche.go
index f2a7e6e2c..65a1f5cfa 100644
--- a/vehicle/porsche.go
+++ b/vehicle/porsche.go
@@ -78,7 +78,7 @@ func NewPorscheFromConfig(other map[string]interface{}) (api.Vehicle, error) {
 		Helper:   request.NewHelper(util.NewLogger("porsche")),
 		user:     cc.User,
 		password: cc.Password,
-		vin:      cc.VIN,
+		vin:      strings.ToUpper(cc.VIN),
 	}
 
 	v.chargeStateG = provider.NewCached(v.chargeState, cc.Cache).FloatGetter()
diff --git a/vehicle/renault.go b/vehicle/renault.go
index 0e956df61..525a60629 100644
--- a/vehicle/renault.go
+++ b/vehicle/renault.go
@@ -123,7 +123,7 @@ func NewRenaultFromConfig(other map[string]interface{}) (api.Vehicle, error) {
 		Helper:   request.NewHelper(log),
 		user:     cc.User,
 		password: cc.Password,
-		vin:      cc.VIN,
+		vin:      strings.ToUpper(cc.VIN),
 	}
 
 	err := v.apiKeys(cc.Region)
diff --git a/vehicle/tesla.go b/vehicle/tesla.go
index 0ce56ef13..88043d952 100644
--- a/vehicle/tesla.go
+++ b/vehicle/tesla.go
@@ -3,6 +3,7 @@ package vehicle
 import (
 	"errors"
 	"net/http"
+	"strings"
 	"time"
 
 	"github.com/andig/evcc/api"
@@ -66,7 +67,7 @@ func NewTeslaFromConfig(other map[string]interface{}) (api.Vehicle, error) {
 		v.vehicle = vehicles[0].Vehicle
 	} else {
 		for _, vehicle := range vehicles {
-			if vehicle.Vin == cc.VIN {
+			if vehicle.Vin == strings.ToUpper(cc.VIN) {
 				v.vehicle = vehicle.Vehicle
 			}
 		}