Octavia II Estate Towbar Install

Part Numbers

Towbar - Bosal 033494
Skoda wiring kit EEA 600 101 EL4A

Introduction

Tow Bar - There is a big selection available on the Internet. Check prices and delivery charges, if you have a supplier nearby, you could save a lot on delivery charges. Tow bars are heavy. I picked the Bosal 033494 as most of it is hidden behind the bumper and only a little part of the lower edge needs to be cut out. The ball is detachable and can be locked in position. It also has a place to link the break away cable to. You will be removing the internal Bumper hidden by the plastic wrap around, so don't be too concerned about the extra weight.

Electrics - Because the Octavia has bulb failure devices and complex wiring you will need to be very careful what you buy. Most suppliers will advise, but you must fit either a 7 way Smart full bypass system, the Skoda wiring kit EEA 600 101 EL4A. or a dedicated wiring kit, otherwise major problems will arise. None of them come cheap and the Skoda kit is almost £200. I probably would have gone for a bypass kit in some form, but I was incredibly lucky that Stu noticed a one off sale item on ebay and I got to buy to buy the Skoda kit very cheaply. The Skoda kit is plug in but it is not an easy job and certainly not for the faint hearted. Making connections to the back of the Fuse Box and to Central Control unit needs a lot of trim removal. The continental 13s fitting means a converter cable is needed to connect to UK 12s and 12n cables, this is another £20 or so. It is possible a bypass kit would be easier as you tap straight on to the battery to bypass the Vehicle wiring and then use connectors onto the rear light/flasher wiring etc. It would also have 12n and 12s sockets. Probably about £50 delivered. Best buy from a dealer who can give advice too.

Tools - You will not need a lot of tools, just a few sockets and a set of Torx drivers. The biggest size needed would be T45. I bought a set of 3/8 square drive for £7 at the local market. Very basic kits are available from £2, but make sure you have a T45 or you will not be able to remove the existing internal Bumper.

Time - Allow yourself plenty, you will have to remove a lot of interior trim to fit the Tow Bar and the electrics. I spent a lot of time finding how to get trim off without damaging it, so this guide may make it a little easier. Store each part you take off with its relevant fittings and with luck you will not have too much over when you finish.

Method

You should disconnect the negative lead from your battery before commencing this job. A 10mm Spanner or Socket should do.

Start by removing everything from the rear compartment. The Spare wheel and all the compartment covers. Fold the two seat backs down.

Remove or loosen a good few turns the 3 plastic nuts holding the rear panel in position, using a box spanner preferably.

Get a long wide flat screwdriver under the trim and prise up the clips, lifting up the rear door rubber seal as it comes off. See Figs 1 & 2.

On the off side. Remove the cover over the T bar with a very small screwdriver. Remove screws and prise away clips etc. See Figs 3 & 4.

Go to the rear passenger door. Remove the outer seat back squab by pushing down hard, unclip the top and lift off at the bottom. See Figs 5 & 6.

Remove the Screw now exposed on the grey plastic trim and go back to the Rear door.

Remove the bag hook screw and a screw where the rear sliding cover normally rests.

These two screws are about the only different design fitted so make sure they go back in the same position, later.

Unclip the small interior light.

You will not be able to remove this piece completely as it is retained by the rear seat belt. Pull out a fair amount of belt, tie and lay on the back seat. See Figs 7 & 8.

Remove screws to free side wall trim. You do not need to remove the T hook screws, although the Photo shows them off, they will come off with the trim.

The fittings around the CD player need to be removed by prising out the middle first and then remove the 3 buttons. See Fig 9.

You should finish up with something like this.

Now do exactly the same to the Near side Trims.

Remove the 2 Hex headed Bolts from either side which go into the Bumper. I think it was 12mm hex socket needed. Longer bolts go through CD player fixing bracket. See Photo above and below. See Fig 11.

Remove the rear light from both sides by unclipping the wiring, pull out the two small lights, unclip the Bulb assembly and remove the four nuts. See Fig 12

Prise out the 4 pins from the centre of the plastic trims on both sides of the Bumper and then remove the studs. See Fig 12 above.

Unplug the rear bumper sensor cable if fitted and pass the cable and large grommet to the outside. Make sure to refit this over the top of the Tow Bar later. See Fig 13.

Remove both mud flaps if fitted. There are four screws in the wheel arch, there is one at the very top where the Bumper joins the wheel arch. It would be a lot easier with the rear wheels removed but it is possible without. See Fig 14.

Remove all the remaining screws from the Bumper lower edge. See Fig 15.

Put down a large dust sheet to protect the Bumper and preferably with an assistant, slide it off.

Store well away from the site. You will need to cut a little off the lower edge later. See Fig 16.

Remove two bolts holding the exhaust rubber support on.

Unscrew the large round nuts securing the heat shield on, the exhaust and heat shield should drop enough to see the two holes that the Tow Bar bolts go through. See Fig 17.

Remove the 6 Torx screws securing the Crash Bar, using a T45 bit.

All that should be holding it now is the underseal/chassis filler. A sharp whack with a hammer will soon loosen it. See Figs 18 & 19.

Scrape any excess underseal from around the fixing area where the Tow Bar bolts will go. You probably won't get much off.

Put the Tow Bar with the Hook brackets towards the ground in the square holes either side and see if the 4 holes match up.

If they do you are lucky! I had to file one hole in the chassis slightly which was out of line.

Fix the off side bolts with a couple of turns first. Fit the near side bolts and if they don't fit too easily a G clamp or similar arrangement should do the job.

Do not get the bolts cross threaded. See Fig 20.

Tighten both sides up evenly using a good quality socket and a couple of extensions. If you have, or can borrow a Torque wrench, tighten to 68 Nm. See Figs 21 & 22.

Make good around the Tow Bar area, underseal would be ideal. Fill the 6 screwed holes no longer used with sealant and treat the Tow bar fixing bolt heads. See Fig 23.

At this stage you need to fit the Towing electric sockets.

These instructions are for using the Skoda dedicated kit but if you are using any other kit you can follow along to get to the Fuse box, where there is a vacant unswitched Live location.

You may not have to remove so much trim if you can pass a guide rod up the front and rear sills. With the Skoda kit you cannot do this as the pre-fitted connector blocks prevent it.

Due to the different mounting point on the Bosal Tow Bar, the length of cable between the socket and large grommet was too short, so remove tape and refit at a good length. The Plastic Bumper has to pass over this. The cable and grommet fit in the off side unused hole. See Fig 24.

Run the shorter part of the cable with the terminal connector and earth to the offside. The much longer cable, runs to the front via the near side.

Insert the two square plastic nuts from the kit, in to the holes in the off side wheel housing.

Connect the multi pin connectors of the harness to the towing control unit and fasten with 2 self tap screws. See Fig 25.

Fit the Earth connection See Fig 26.

You can now replace the Plastic Bumper but first of all cut out an area from the centre of the lower edge. 70 deep by 55 according to the instructions but this is not enough for the Cable so make it bigger. It is difficult to find the exact centre of the Bumper so a bit of trial and error is needed.

Run the parking sensor cable over the top of the new Tow Bar and refit and re clip. See Fig 27.

Make sure you have run the longer cable towards the front along side the existing wiring and not through the rear suspension strut. At this stage I took a break and refitted all the trim so far removed as installation is finished in the luggage area. Re assemble in reverse order.

Points to look out for -

When tightening up the Plastic Bumper fittings get someone to sit in the middle of the Bumper or it can foul the bottom of the door if it set too high.

Now it's time to make the connections to the Fuse box and Control Box

The trim should be removed in the correct order as a most of it is interlocking in some way.

Pull out the light coloured trim on the pillar between the Driver's and Passenger's Doors. Just enough to unhook from the metal retainer. Do this on both sides of the trim. Then ease off the two pins at the top. The seat belt prevents complete removal. See Figs 28,29,30.

The lower pillar trim will now unclip, slip out from under the Passenger's sill moulding. Look out for the internal alarm sensor wiring and unclip. See Fig 31.

Remove the Passenger's sill moulding. One screw, slip off of the two retaining pins, the large plastic nut and then the moulding slides towards the front and off. See Figs 32 & 33.

Next you'll need to remove the bonnet pull. This can be quite tricky, pull the lever as if to open the bonnet and you'll see a locking tab on the back of it. This tab should be levered out using a flat blade screwdriver and the bonnet pull should slide off.

Remove the large Plastic nut and the Trim will unclip. See Fig 34 & 35

To remove the bottom part of the Instrument panel, firstly remove the headlight switch, this is done by pushing the knob in at the same time as turning to the sidelights position, withdraw the switch and disconnect the plug.

Prise off from underneath, the two silver trims. Remove the screws underneath. See Fig 36 & 37

Remove the Fuse cover and remove the screw located underneath it. See Fig 38

Slide a thin screwdriver in to the very top of the diagnostic socket to release the catch and push through towards the front. Mine had a very short cable and it is a little easier to remove from lower Instrument panel first. You can just see it on the right of Fig 40

Remove the rest of the screws holding on the lower Instrument panel and pull off. See Fig 39

Remove the polystyrene sound absorber and one screw holding on the heater tube. See Fig 40

Before you go any further make sure that the Negative lead is removed from the Battery and is well clear of the Terminal. You will find that when you reconnect the Negative lead the Radio does not lose its coding but a steering warning light may come on, This can be cleared later by driving slowly in a straight line.

Unless you are fitting the Skoda wiring kit you can got straight to removing the fuse box to get at the vacant positive tongue. Fig 42, 43, 44.

For Skoda kit wiring. Unclip the the Central control unit on the right first. You can just get to this clip between the Fuse box and the door pillar with a long screwdriver. It should drop down a little when disengaged. See Fig 40.

Unclip on the left and the box will drop out downwards. You may need to cut a cable retaining clip to be able to turn the box upside down to fit cables.See Fig 41 & 42.

Remove the two screws holding on the Fuse box. Drop down and unclip the back cover. See Fig 43 & 44.

You can now fit the towing harness, follow the included instructions exactly. You need a very thin screwdriver to unlock the cables from the connectors. You can practice on the towing cable and six pin connector supplied.

To make it a little plainer as the Instructions could be better. The terminal connectors are held in place by the red locking bar you can see in Fig 44 above. This needs to be slid to one side to unlock. Then the connectors will pull out. The circuit board is marked E F G H

Terminal block E is numbered so wire E2 is on block E position 2

Wire G7 is on terminal block G position 7

Wire G8 is on terminal block G position 8

Remove the wires as instructed and insert in to the numbered 6 pin multi connector, in the correct positions.

Fit E2 G7 G8 from the towing harness in to the now empty positions.

Refit the connectors and relock.

To fit the wires to the fuse box you need to unlock the purple plate from the body to get the wires right home. They then become fuse holders. With the black clip (Arrowed) held off, the purple plate will move a little, enough to get SB43 SB44 SB45 SB11 into the lower positions. The bridging harness goes in the upper positions and the feed connector goes to the vacant tongue on the bus bar at the back of SB22. (Arrowed)

All the connectors should click when home and if they are being difficult I found that feeding them on to a fuse blade while pushing from the other side kept them straighter. Relock the purple plate when you are sure the wires and fuses are fitted correctly.

The connection at SB11 remains a bit of a mystery as there is nothing providing power at the other end of the fuse. I tried putting a positive supply through but it did not seem to operate anything and all the towing functions work fine, apart from the turning buzzer. Also the wiring instructions show another fuse in the same row and I have nothing there. If you can explain please let me know. See Figs 44 above and 45 below.

Refit the back on to the fuse box,

Refit the Control box, Turn it up the right way. Push up the left side first and click in to position.

The Electrics should now work. Refit the Battery cable and test with a trailer board or similar. The Towing function has to be activated using Diagnostic Equipment VAS5051at your local Skoda dealer or by somone with a CANBUS capable VAG-COM lead to get it fully functional. This is to turn on the Turning Indicator Buzzer and to cut out the rear parking sensors when Towing.

If all is well replace everything in reverse order.

Remembering that the Diagnostic socket wiring goes above the polystyrene sound absorber.

Refit the lower part of the Instrument panel. Refit the remaining trim in the correct order.

Many thanks to Stu. for his help. I believe I have everything down in the right order but don't trust this article completely.

Happy Towing.

Best wishes,

A.W.

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