451 DRL Options

Pre-Facelift DRLs

The first type of daytime running lights available for the 451 was this type.

They consist of a pair of Hella lights and surrounds. Smart part number A 451 820 00 61.

However, if you buy them from smart, they’ll be ridiculously expensive. So, do a Google search for LEDayFlex. The prices fluctuate but the kit can be bought for as little as £40.
Click here, here or here for examples.

Now you have an option of the surrounds.

Original 451

A 451 820 07 18
A 451 820 08 18

Facelift* 451

A 451 820 13 18
A 451 820 14 18

What’s With The Asterisk?

The original design matches the original grill design. The facelift design matches the facelift grill design. However, the facelift grill came on cars with a different splitter on which these surrounds won’t fit. However, if you fit the facelift grill but keep the original splitter, the facelift type will match.

You may also require the extra adapter wiring harnesses, it depends on the year. A 451 820 06 04

Fitting The Hella DRLs

Here is a complete set for 1 side of the car.

Each light pushes into the holder…

…and the supplied bolts go through the holder and into the lights to hold them securely.

Install and tighten all 10 bolts.

Then you need to secure the the holder to the surround using the supplied 3 screws.

Tuck the wires safely over the tabs to secure them out of the way.

Then you can clip the waterproof connector into place.

Repeat for the other side and you’ll have a complete pair.

Pull out the existing covers. These are fairly easy to push out from the back.

Look inside the hole and you’ll probably see a 2 pin yellow connector. Hopefully you won’t need these. These connectors are for the fog lights but some cars can be coded to use these connectors for DRLs. If you only have these connectors, you’ll need the previously mentioned adapter wiring harnesses.

Have a good look around behind the front panels for a spare 3 pin connector. They will have a blanking plug in the end that needs removing to reveal the red connector.

Plug the black box (LED driver) into this red connector and route the other connector…

…into the hole that the surround will cover.

Plug the DRL in…

…and push the surround into position.

Repeat on the other side…

…and turn on the ignition.

The DRL’s should come on with the ignition and turn off when you put the headlights on.

I Have These But Some/All Have Failed

Have a look here

I Don’t Have The Red Connectors

You need the adapter wiring harnesses that plug between the fog light wiring and the black box (LED driver). However, before you rush into it, get your car checked for compatibility. If your car’s SAM unit doesn’t have the fog light relay in it, your car can’t be coded for DRLs.

The SAM unit uses the relay for either fog lights or the DRLs, it can be coded for either but not both.

BUT…

Just because your car has fog lights, doesn’t mean the car can be coded for DRLs. The early SAM units didn’t have ability to be recoded for DRLs. So, like I said previously, get your car checked on an MB Star machine to see if it’s compatible before continuing.

Facelift DRLs

A 451 888 06 23 Lower grill for DRLs.

A 451 540 75 08 Wiring harnesses
A 451 906 03 51 Left DRL
A 451 906 04 51 Right DRL