If you have E-code lights in your E21 with the 4 watt City lights, you can wire the city light bulb to function as a daytime running light.

The following diagram (sorry for the handdrawn quality) shows how to wire the city light to come on any time the ignition is in run and the ebrake is released, and is wired through a switch for override. There are other ways to wire this.

The key is tapping into the ground line for the ebrake/brake fluid dash light, and installing a diode the correct way.

Specific Instructions

Do you want to add daytime running lights that come on when the ignition is on and the E-Brake is off?
These instructions add this capability while only adding one relay. Your ebrake, dash light, and brake fluid level switch will not be affected, and the brake fluid switch will not interfere with the daytime running lights.

1. Find the lead coming from your ebrake to under the hood. It is brown and blue. Tug on it to make sure you aren't looking at the one that runs from the brake fluid resivoir to the dash.
2. Cut this wire near the firewall, and wire it according to the diagram. Basically, connect the wire running to the firewall to the negative ends of two diodes.
3. Connect the positive end of one of the diodes to the other end of the wire you just cut that runs to the fluid resivoir.
4. Connect the positive end of the other diode to about four feet of wire. This wire will run to the relay as shown.
5. Wire the relay as shown below. You may want to wire the relay a little differently if you are running lights that are stronger than parking lights. (i.e. Run the switch to a simple four point relay between the "s" on the switch and the 30/86 connection on the main relay).
6. Connect your running lights to the relay as shown.
7. Run the wire that runs from the 30/86 terminal of the relay to the dash so you can connect a switch. I used a standard (early) fog switch.
8. Make sure everything is wired as shown. The dash switch is a master switch. It is not necessary if you don't want one.

Good luck!        If you have any questions, email me at admin@e21bmw.net