Deeplink Tips & Tricks: Turn signal

In 1996 VW introduced a longer front to their T4 which was necessary to accommodate the VR6 engine. As well as the longer front, VW changed the turn signal glass from orange to white (except for models in the USA and Canada).

VW unfortunately did not supply the turn signals with nice bulbs (fried-egg-optic). In the picture to the right you can see the original way VW sold the T4.

Anybody who has re equipped their T4 turning signals with short front, white turn signals or clear glass turn signals might have the same cosmetic problem.

Fortunately there are a lot of manufacturers providing bulbs with chromium coatings (also known as chromium-plated turn signal lights). Many car accessory companies sell these under different names.

When I bought my used T4 in 2003 there were Osram Diadem bulbs in the turn signal lights. They have a light blue shine when they are not lit up. In use they flash orange.

At the end of 2007 one of those Osram bulbs was defective and I had to look for a replacement.

Meeting other VW drivers and owners, gave me a chance to see lots of different turn signals bulbs. There were some that did not have the previously mentioned (blue shine). After asking a few people I was advised to buy Philips Silver Vision.

On the following pictures you can see the two previously mentioned bulbs compared with each other:

Inexpensive bulbs are very easy to find here in Germany on eBay and other online stores but the cheapest ones do not have a homologation (the E-number is missing or fake). These are so called ‘goods from China’. I couldn’t say how long the bulbs would last due to my lack of experience; having said this, the 15-20 euros (approx) that I paid for my pair of Philips Silver Vision bulbs is significantly different to the 3 euros you pay for the bulbs from China. But for me, my car lights are important elements of security. You wouldn’t want to have inexpensive brakes made out of granite and wood would you?

Some more pictures of the bulbs:


Above on the left the Philips Silver vision, on the right the Osram diadem.

Placed in front of a desk lamp, both bulbs shine orange, just as they flash. They work just the same as an installed classic, orange coloured bulb. Even laying on a piece of white paper you cannot see that they actually have different coloration while not in use.


They look different when not in use or with no emission of light in the back of the bulbs. The Philips bulb (on the top) appears in true chrome optics. The Osram bulb (on the bottom) appears with the bluish-orange colour. The orange may appear due to some reflexion from the Philips bulb behind of it.

On the first picture you can see the noses (the pins) are slightly offset. These bulbs fit into the socket BAU15s. Most importantly is the »U« in the name on the base; other bulbs (not flashing in orange) do not fit in this socket.

The normal, white bulbs used in turn signals (and also in other applications) fit into the base BA15S. If you buy clear glass turn signal housing or a housing of without orange tinted glass you have to make sure you buy the right bulbs for the right socket. The old bulbs do not fit in the new socket.

If you buy a housing without the removable socket, your new orange bulbs will not fit in the old socket. In this case you have to remove one pin from the bulb and solder on a new one. But this alteration is not recommended.

translated by [dan] (17. Aug. 2008)