Interior Update: LED Lights

One of the most distinctive aspect of older cars are the analog gauges they use. In the G-Wagon's case, the exterior has not changed at all since 1979, but like every other car, the interior has been updated. Many will say, the greatest advancements in auto design over the last 50 years has taken place in the human interface. I really like 70's style VDO gauges in the early G-Wagons but like just about every classic car, they are really hard to see at night. Most modern cars have advanced illumination that utilizes Light Emitting Diodes (LED) or Cold Cathode Fluorescent Lamp (CCFL). LED and CCFL are a much whiter, brighter, more efficient and cooler light source than the incandescent bulbs in the older G-Wagon dash. 

T5 Dash Light LED vs. Incandescent 

In most cases, upgrading lights in the dash to LED is as easy as finding the correct light and simply replacing the old lights with the new. In the G-Wagon most of the lights are pretty easy to install, but some require a bit of work. Most folks will want to do them all at once so the whiter color will not stand out against the yellow color of the old bulbs. 

Replace the old incandescent bulb with an LED version arranged as a Surface Mount Device (or SMD). The lights are inexpensive and easy to find. Simply search online for SMD and the bulb type: like T10 SMD. When ordering remember the bulb type refers to the base and not the amount of light or the configuration of the bulbs. Make sure what you order will fit! How much are they? Prices are falling fast but a 10 pack of SMD T10 can be had for about $11.

There are basically 3 types of bulbs used in the interior of the early G-Wagons:

T10 - Large Bulbs for Dash - 2 in the Speedometer, 1 in the Odometer and as parking lights in the Euro headlamps. (More on hi/low beams later)

T5 - Small Bulbs for Dash - 4 used in the climate control console, 2 for illumination in the dash combo cluster 

23312 - 2 each in the dome lamps and also 3 used for the license plate

1156 - Used for Backup Lights

Rear W460 Cluster with Bulb Locations

NOTE: The T5 and T10 are also used as indicator lights. In some cases like the charging light, the indicators use the resistance of the bulb to function properly. LED lamps use much less energy so they have much greater resistance. Additionally if you use them for things like the blinker, they are so bright they can be distracting. I would recommend resisting the temptation of going overboard with the LED replacements and stick to bulbs used for illumination. 

LED NOTE: LEDs are based on diode technology. That means that, unlike incandescent bulbs, LED lights are polarity sensitive. If you install them backwards, they will not work. If you install an LED and it does not work, simply remove it and turn it around. 

Don't install any of the bulbs with the power on. Turn the source off first, install the bulb, then test. You won't electrocute your self, but you will be replacing some fuses!

Most of the bulbs are very easy to get to and replace. You don,t have to remove the gauges but if you do, simply push from the back and they will pop out. The T10 Bulbs for the speedometer is very easy to replace. Simply pull the socket from the back of the gauge and pop the bulb out. Make sure you put the socket back into the guage for testing because it grounds only when installed.

The T5 bulbs used in the fuel/temp combo gauge that are mounted in screw off sockets and are MUCH harder to swap out. Also a bit more difficult to find is the shifter bulb that is used to illuminate the fiber optic spider assembly. To replace those with LED lights, you will need to modify the bulb to work. 

The dome lights may be the easiest to install so that is a good place to start. Simply pry off the dome light from the side opposite the switch. Remove the existing bulb and install the new one. DONE! Now you can really see when you open the door. 

Modified T5 LED Dash Bulb

On the combo gauge, start by finding taking the black socket and turn it clockwise until you can pull it out. You will not have to remove the gauge to do this. For the cluster lights, you will need to remove the T5 bulb from the socket. This is really hard to do without breaking it. use rubber gloves to glove for better grip while gently rocking the bulb side to side while pulling. Don't use tools because the bulb will break and it will be very difficult to remove from the socket. 

If you try to simply plug in the replacement T5 bulb you will find it does not work. I had to modify the bulb by wrapping and soldering thin solid copper wires to each side of the bulb. Even if you are very good with a soldering iron, the bulb may now be thick too plug into the socket. Take a file and carefully file off the excess solder and some of the thin wire on the flat side. Make sure not to cross the leads on the same side of the board. Test your work with a 12V source PRIOR to installing in the socket and again after you pul the bulb in the socket. 

Now you are ready to put the bulb back into the cluster. Repeat this process for all both socketed T5 bulbs you are using. 

Complete LED Dash Upgrade

My W460 has parking lights in the Euro headlights. The LED lights look great in there but are a bit difficult to replace. Remove the headlights, from the car and take them to a work bench. The sockets may have been sealed with silicon glue. Carefully cut away the glue until you can remove the socket and the T10 bulb. Put in the new LED bulb and seal with silicon glue. You may need to trim away some of the metal if your bulb is large.

If is very easy to replace the 1156 lights in the backup lights. This provides a brighter, whiter illumination when backing up. Simply remove the two screws on the rear lights and install the new bulb. Remember, if it does not work, remove the bulb and turn it around. 

Another upgrade was replacing the license plate lights with the same lights I used in the dome. The only issue is, they are so bright that the license plate was too bright for me. So I only use the center of the three bulb and leave the other two empty. 

Once you replace all the bulbs everything will look great. The bonus is these lights use a LOT less power. So if you leave your door open, dome light on, or even the parking lights on -- it will be a LONG time before you drain a fully charged battery. 

Enjoy your updated look and try not to stare at your great new dash while driving at night. KEEP YOUR EYES ON THE ROAD.