451 Aftermarket Stereo

451 Fortwo Aftermarket Stereo Fitting

You will probably be replacing 1 of 3 types of smart stereo.

The original stereo, double height with no touch screen. (Radio 9 or 10)
The facelift interior single height with no touch screen. (Lowline)
The facelift interior double height with a touch screen. (highline)

Pre-Facelift Radio 9 & 10

Each one of these will require a specific replacement stereo surround to match the hole in your dashboard. I was replacing a Radio 9 so I got the correct surround for this job. I screwed the side panels in place…

…and slid the replacement stereo in from the rear.

Line it up and use the screws provided with your head unit to fix in in place.

Many aftermarket stereos have unusual connectors but they will always come with an adapter.

Quite often, the adapter will have bullet connectors that can be swapped around, however…

…the smart has an unusual layout for the connections so you’ll probably have to swap them around to suit. Looking at the numbers moulded into the connectors, you can see that the standard smart connector (top) has connections for 1, 3, 4, 5 and 8. But the new stereo (bottom) has connections for 4, 5, 6, 7 and 8.

If you don’t swap them over, the stereo may not turn on. Check the new stereo connections and compare it.

In this instance we need to swap 2 wires.
Red wire (switched live) pin 7 to position 3.
Orange/white wire (lighting input) pin 6 to position 1.

If you flip the new connector around and view the pins. You need to push something long, thin and strong down the hole (arrowed below) to flatten a small metal tab. With the tab flat, the connector can pull out.

Here I have used a dental tool but you can get proper terminal removal tools.

You can see the metal tab that has been flattened down.

Get a knife behind it and carefully lever it back up. You can now slide the terminal back into the correct position in the housing.

There is a good chance that the ISO aerial connector of the smart won’t fit the DIN connector of the stereo.

So you will require an ISO to DIN adapter. Cheap on eBay.

Push the adapter in and your existing aerial connector will just push onto it. If you have any other connections such as DAB, GPS etc, do these now. Connect the power and speaker connections also.

Slide the stereo construction into the dashboard.

If the switched live is wired correctly, the stereo should come on with the ignition.

Set the time and some favourite radio stations. Turn the car off and then back on again. If the permanent live is wired correctly, the stereo will remember the time and station settings.

If everything is OK, screw it to the dashboard.

Place the cover surround around the stereo and replace the lower hidden screw.

Replace the button bank and you are done.

Highline Replacement

If you have a failed Highline Bosch touchscreen stereo…

You can actually use the existing surround, unbolt the old stereo and bolt in a replacement double DIN stereo. There’s more about that here.

Do NOT bother with the aftermarket Highline fascia replacements, they are so shit.

Lowline Replacement

The Lowline stereo has a different shape so there are separate replacement surrounds for it.

So, what we will be doing is using the superior Lowline replacement surround and adapting the car to suit.

Screw the brackets onto the fascia.

Slide your new stereo into the back until it’s flush at the front. Screw into the side, through the brackets and into the stereo. The stereo bought was a Pioneer AVIC-F88DAB. Pioneer are so much better than the cheap Chinese units.

Plug everything in and slide the stereo into place to make sure it fits ok. You’ll probably need a DIN to ISO radio antenna adapter

. Your old Highline trim is no good…

The standard screws that held the old stereo in will fit the lower hole but not the upper. That’s fine.

…you need the standard Lowline trim direct from smart or 2nd hand on eBay. The smart part number is A4516891337.

Slide it under the stereo…

…and clip it into position.

Depending on the features your stereo has, it’ll probably have a rat’s nest of wires.

Most stereos come with bullet connectors for the switched live, permanent live and remote live. When you replace the Highline or Lowline, these are usually OK as it is.

Turn on the ignition and make sure the stereo goes on and off with the ignition. The speakers work and the features work.

Fitting The Microphone

There are a few good places to put the microphone, assuming your stereo has the ability to attach to your phone. Most touch screen stereo do have this option so you can make hands free telephone calls. Remove the front interior roof trim and the A pillar trim.

That gives you a gap to the side of the dashboard that will allow you to run cables under the dash.

Tape the cable to the metal so it’ll all be hidden when you replace the trim pieces. One option is to clip the microphone to the top front trim, in the centre above the interior light.

Secondly you can wire it a bit further and use the sticky pad to stick it to the trim above the door.

However, my prefered fitment is helped by the Lowline fascia adapter. Look either side of the screen. Vents.

Behind these vents are tubes…

…which are perfectly designed for most microphones. They just push in.

I like to use a little hot glue to make sure it’s not going to rattle.

Thread the cable through the opposing hole…

…and refit the fascia. You can just make out the microphone behind the vent.

DAB Antenna Fitting

The majority of DAB antennas are passive so it’s as simple as plugging in 1 connector. No power or earth. The one I got with my Pioneer was a stick on generic one, like this one here.

 This is how I fitted mine, along the top of the windscreen. the box was hidden and it looked neat. Do NOT do this. What I found out afterwards is that DAB transmissions are vertically polarised.

That means a horizontal antenna isn’t going to do a good job of collecting a signal.

So, to mount it vertically, you need to place it on the side of the windscreen. That can be good or bad depending on what A pillar covers you have. On this car, I have the low profile covers. There is absolutely no room underneath this style of cover to fit the DAB antenna. So the box will be on show.

If you have the full A pillar covers (shown below), there will be room to hide the box and just have the antenna showing.

I plan to fit the full covers and reposition the DAB antenna on the side since my horizontal reception is terrible.

Din To ISO Radio Antenna Adapter

Most aftermarket stereos have a DIN style connector. Like a banana plug.

However, the smart has an ISO connector. Like a press stud. So you need an adapter.

I bought this one from Amazon. I prefer the longer type to the stubby type as they are less likely to disconnect.

DIN to ISO Lead – Link

Plug it in…

…and connect the other end to the existing wiring.

Done.

GPS Antenna Fitting

If you are replacing the touch screen Highline stereo, you already have a GPS antenna. There may be an issue though. The standard GPS antenna uses a FAKRA C (blue) connector.

However, on the Pioneer stereos, they decided to shun the standards and go for an HRS-F connector.

So, of course you need another adapter. GPS Antenna Adapter Fakra to HRS-F

Plug it between the stereo and the existing GPS antenna connector and you are good to go.

If you don’t have an existing GPS antenna already fitted, you’ll have to add one. The best place to put it is up high (unless you want to remove the dashboard). So, as before, remove the internal roof trims so you can run the wire up behind the A pillar.

If you have a GPS antenna head with a magnetic base, great. Put it between the roof and the metal. Refit the trim.