Buyer's guide Common Issues on the MK3 Leon

Work in Progress

SEAT LEON MK3 – COMMON ISSUES

Below are the issues I have seen on both the Web and this forum that pop up time and time again.

1/ Front LED Lights turning foggy

Does not cause MOT Failure but looks like there is something on the inside of the light fitting check out https://www.seatcupra.net/forums/threads/headlights-haze-on-glass.456234/#post-4879806 there is also a link to a much longer thread on the subject.

2/ Rear Indicator Issue – Water Ingress

• When the cars were new this was a common problem as the rear lights had been over tightened causing the lights to crack
• Now the cars are getting older the rear light seals may need replacing or it could be caused by pressure washer forcing water in see https://www.seatcupra.net/forums/threads/2019-leon-rear-indicator-issue-water-ingress.482184/

3/ Heater Matrix needs replacing

• Some people see this first because the heater stops producing hot air across the board or on one side
• Others have issues where they are leaking coolant, on the Diesels this is often seen after the DPF Regen occurs

How to replace can be found on multiple post on the forum but one example https://www.seatcupra.net/forums/th...ething-problems-but-sorted-in-the-end.476713/

4/ After Replacing Battery the dashboard lights up like a xmas tree

• Take the car for a drive and the errors will self clear
• Turn steering wheel all the way to the left and then all the way to the right can also clear all the errors

5/ Water in the boot spare wheel well

• Water can get in from sunroof drain plugs
• Water can get in from worn rear indicator seals
• Water can get in from rear air vent (one each side)
• Water can get in from the rubber covering for the electric cables into the rear door
• Water can get in from rear washer connections
• Water can get in from the fuel filler https://www.seatcupra.net/forums/threads/water-leaking-into-boot-through-fuel-flap-unit.477670/
• Water can get in from front doors (yes front doors) check out https://www.seatcupra.net/forums/threads/pool-of-water-in-spare-wheel-well.435394/#post-4699386 for more info and Youtube link

6/ Water Pump

Very common issue on these cars, starts as a slow leak as there is a lot of plastic in the pump it breaks down and leaks.

7/ Parking Sensor issues when near Renault group motors in slow traffic

Seen a lot on Pre Facelift not sure about Facelift cars but the parking sensors are upset when close to a renault in slow city traffic check out https://www.seatcupra.net/forums/threads/parking-sensors-mad-at-renault-group-cars.481828/

8/ Fuel Flap Actuator failure

1. To be aware of you can code the actuator so that it does not auto lock every time you drive off, this reduces the number of times its used and increases the life of the actuator
2. check out
   its a very simple replacement process and make sure that the end of the drain pipe is in the wheel well not inside the arch liner.

9/ Seat Bolsters on cars post 2014

1. The White Plastic trims used to crack but also later seats had the same issue check out pictures here https://www.seatcupra.net/forums/th...k3-leon-do-today.379107/page-459#post-5011352

The following information is from the OBD11 Car health report under Car buying assistant









Please feel free to add in the comments and I will update the Resource so we have a complete list all in one placve.