Heater not workingc

How wet is the foot well? This is likely to be one of two things. Door seal rubber or the Heater matrix.
Try this bit of detective work. Does it only get wet when it rains heavily? Is it just the front that is wet? Feel the carpet in the foot well. How high up the foot well carpet does the wetness go? Does the wetness smell of anything? Do you have a sun roof fitted? Sun roofs have drain holes that can clog up so the rain pools up in the grooves and runners then over spills inside the vehicle.
If it only gets wet after rain it could be a worn out door seal rubber or the sun roof letting water in. Door seals usually cause shallow pools of water so the wetness won't rise very high up the carpet. The sun roof sometimes causes the seats to get wet as well.
If it is wet all the time, the wetness rises high up into the foot well and it has a 'sweet' smell, it could be the small radiator unit,(the Heater Matrix), behind the dashboard that supplies heat to the heater blowers leaking. Depending on where exactly it is fitted you'll sometimes get wetness in both front foot wells. The smell is the coolant from the engine.
Hope this helps.

If it is inside the car in one footwell it will be one of three things. It will be either a leaking pipe to the rear windscreen washer jet, a worn door seal rubber or the heater matrix behind the dashboard.
Get into that footwell and using the back of your hand start at the floor and feel the carpet for wetness. Work your way up the carpet towards the underside of the dashboard. Your looking for the point where the carpet goes dry. Try this near the centre of the car and nearest the door. Floor only suggests washer pipe. Wet around the door is possibly a door rubber and high under the dash is most likely the heater matrix. This may seem an odd question but does the wetness have a smell? A rotten egg smell suggests screenwash. A sweet smell could be coolant.

sounds like heater core could have a restriction

Air lock in heater matrix, or matrix clogged with sediment. Is water level ok, is coolant clean?

Heater controls malfunction.

Water pump faulty/belt slack.

low level of heat could be thermostat jammed open.

Blower motor inoperative/slow?

Hi, look at this way ,,,, it's wet on both sides on the inside of cabin. Gravity being what it is , check the heater cowling below the heater matrix for (water) dampness. On a bad day there are only two hoses coming thru the engine bulkhead ,,, to the heater matrix , so do the maths yourself . A pressure tester will expose any weak / vunerable hose connection. Good Luck

waterpump or water leak. check your water levels, and turn the heater temp up, if its still cold then there is either a problem with your heater matrix, air in the system or water pump is knackered. to check for air pockets in the system take the cap of your water bottle and let the engine run for 15 mins. this will let any air pockets escape, and remember to check the water level afterwards. if you heater matrix is gone then you would probably find that no hot air comes through or their are wet patches in the front passanger and driver carpets.

Hi these could be unrelated, firstly check the heater blower fuse I had an A4 and the fuse had melted stopping the blowers from working, Im assuming yours is the digital type? anyhow if its not the fuse then Im afraid you have a more seriuos problem with the water on the floor it sounds like the heater matrix has burst this is the small radiator behind the dash that circulates the hot water for the fan to blow in. Although the water could be coming in from under the bonnet this is common on vw/audi's just under the windowscreen with the bonnet open below the wipers you will be able to see down into skuttle panel they sometimes get clogged up stopping the water from running off, and into the car instead there is small drain holes you will be able to see upon inspection leafs and muck normally clog them up.

If it is the heater matrix then it will be quite expensive!

Regards

Dan

hi assume this water ? you are saying on floor have you ceck your coolant level? if it is low ? there is a possibility that you may have a leak on either heater hose where it connects to heater matrix or the matrix itself has popped a core and is leaking try feeling if carpet is damp around the heater area under dash ?

these suffer a bad heater matrix, the carpet gets wet.
head gasket, water goes brown.
water leak, under exhaust manifold a black steel pipe it pushes into block, there is a recess to hold an o ring on it rots away and leaks when driving making it hard to find, dont use rad weld as blocks heater matrix on these cars.
see if you have a water mark around the bottom pulleyas poss a leaking water pump, it will leave a white or brown mark around the pulley closer to the bulk head.

The 405 is renowned for having the heater matrix go bad and often it springs a leak woth an associated slooshing sound. Heater matrix is like a mini radiator which is fed by water from the engine and is located behind the dash.

It is located on the lower left hand side of the dashboard. If you look under the glove box and in towards the direction of the centre of the car you will just about see it. Check the area around passenger floor and closest to the centre console for any dampness on the carpet or signs of leaking. If this is evident you have found your problem.

One solution is replacement from breakers though companies can be found who specialise in radiator repair and if you can find one in your area this is an even better solution.

Slooshing water noise like you describe is sometimes associated with impending head gasket failure but I would check your carpets first for dampness and eliminate the heater matrix first owing to it being a known failure point on the 405.

Hope this helps.