How to flash parking lights on a Mercedes?

two relays are required for an independent parking light circuit:

Relay # 1:

• 87 & 85 : Light Output from alarm/RS unit
• 86 : Ground
• 30 : To left side of parking lights
• 87a: NOT USED

Relay # 2 :

• 87 & 85 : Light Output from alarm/RS unit
• 86 : Ground
• 30 : To right side of parking lights
• 87a: NOT USED

Just split the alarm's parking light output with a pair of six-amp diodes.

Tie the alarm's parking light outputs to one end of both diodes.

Now you have one end of each diode left over; these go out to the left and right parking lights in the car.

(I can never remember which way to orient the diodes.  Just try it temporarily by holding the diodes in place with your fingers, and then reverse them if the parking lights don't work.)

Jeff's setup with the two relays will also work fine, but in my opinion, it is too expensive and inconvenient.  Relays will cost anywhere from $2-20 each depending on where you shop, plus the labor to wire them up and mount them.  You can get a whole package of diodes for a buck or two.

You do suffer a very slight voltage drop with the diodes.  The parking light flash will be just slightly less bright than if you'd used the relays; not enough to even notice.  And, of course, when you use the normal light switch on the dash, they'll still work just as brightly as ever.

Hey Chris.... he/she drives a Mercedes.... I don't think $$$$ really makes a difference to him/her . I never thought of using the diodes and splitting the parking light wires . I've always used 2 relays just to be sure as diodes have a higher tendency to burn out than relays.