Mk4 Indicators Onto My Mk3 Astra

How I Fitted M4 Astra Side Indicators onto my Mk3 Astra

This is quite a simple process and can be done by most people with a little knowledge and patience. The tools I used included a Jigsaw, Stanley Blade, Soldering iron and equipment, heat shrink, masking Tape, insulation tape and double sided tape, The task can be completed in less than 1 hour without rushing and is well worth the effort.

The total cost is less than £20 including all parts.

The parts I needed were 2x Mk4 Indicators (approx £9 the pair from Vauxhall) and bulb holders to suit. I also needed a small part of the wiring loom. I already had the bulb holder and wiring loom in my spares box though it's easy enough to get the parts from a scrap yard because you can then get the bulb holder and the wiring loom with that little bit of extra wire to play with to make the job much easier.

New indicator

+ wiring Loom

The new indicators have lugs on the underside for them to clip into the Mk4 Wing, I am going to remove these lugs and have the underside smooth, they will firmly slot into the wing of the Mk3 with just a touch of Double sided tape to keep them in place.

Masked Off

Using a Blade

Step one, I Masked the edges of the indicator and removed the bulk of the plastic lug using a jigsaw, then using a Stanley blade, I began to scrape away thin layers of plastic, I finished it off by using the soldering iron to melt the last remaining bit of plastic down. Doing it in stages resulted in a neat and tidy finish.

Making it Flat

View the Side

Step Two, I Removed the original indicator lens from the car, then I pulled out the bulb, removed the rubber seal, then holding onto the biggest lug, I pulled the plastic moulding away from the car slightly, It is held in by 2 clips behind, these clips are shown in the picture-located at the top and bottom of the unit, these need to be pushed in with a screwdriver to enable the unit to be released from the wing.

Cap Removed

Unit Removed

Step Three, I Snipped the unit off and bared back the wires ready for soldering (TIP Be ready to place a rag into the hole of the wing to prevent the loom falling inside the wing). I then Fluxed and Soldered the wires. I also Prepared the new part of the indicator loom with flux and solder and then soldered the two looms together (TIP join the wires by hand first and check everything works fine by putting on the hazard lights).

Trim Wires

Soldered

Step Four, I Covered the soldered joins with heat shrink then wrapped the whole loom in insulation tape to prevent moisture damage to the wiring.

Insulate the wires

Step Five, I Connected the indicator into the bulb holder and positioned it onto the wing to test fitment. My drivers side slotted in perfect, the passenger side just needed a touch of plastic shaving from the body of the indicator using the Stanley blade. Never presume they will fit perfect the first time.

Test for Fitting

Step Six, When I was satisfied that the indicator fitted perfect, I positioned a thin piece of double sided tape to the underside of the indicator then attached it to my car (TIP the indicator needs to be removed when replacing bulbs so I did not go overboard with the tape).

I then Repeated steps 1-6 on the opposite side of the car.

Finished Product

The information I gave above is the process I used when fitting my own indicators, If you wish to repeat the steps on your car I can accept no responsibility if things should go wrong for you.