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Discussion Starter · #1 ·
Many thanks goes to Dave Handa

Many thanks goes to Dave Handa and Bob Bowser for this excellent procedure, and FCA NW Region for posting the article for all to benefit.

How do I turn on my 308 parking lights without having the headlights pop up?

Many 308 owners would like to be able to run their parking lights without having their headlight buckets in the up position. While Ferrari made this possible starting with the 328 series, many earlier 308 series owners would like to know how to update the headlight circuit so that the headlight buckets can be down when the parking lights are on. Follow these easy step-by-step instructions to make the modification. For those interested, included at the end of this FAQ is a brief explanation of how the circuit works and exactly what is being modified.

Materials You Will Need

2 each 200 volt/1 amp silicon diodes (available from Radio Shack)
2 feet of 14 gauge electrical wire
2 each crimp-on taps for the 14 gauge wire (it's best to use the taps that accept a female spade terminal)
2 each crimp-on male spade terminals (to attach to the taps)
An assortment of heat shrink tubing
Some electrical tape
3 each crimp-on butt splice
3 wire ties to keep the new wiring tidy under the dash
Making the Modification

Remove the fascia cover from the dash (the power portion of the passenger side dash). This will reveal an assortment of fuses and relays. Keep the fascia cover handy, as you will need to refer to the diagram on the back of the cover throughout the following steps.

Locate the head lamp lifting motor relay. There are three headlight relays: one for the left, one for the right, and a third which drives the other two. The one you want is labeled "Head Lights Motor Contact", and is located in the center of the panel. Check the diagram on the back of the fascia cover to make sure you've got the right relay. The connections on the relay are labeled as follows:
85 - Control Input
86 - Control Output (usually ground for the solenoid)
30 - Power Input
87 - Primary Power Output
87a- Secondary Power Output

Note: When 12 volts are applied to the Control Input, the solenoid is activated, and connections 30, 87, and 87a are shorted together.

Identify the fuses for left and right high and low beams. They are usually the first four fuses in the right panel.

Unhook the relay panel by lifting and rotating the top toward you.

On the back of the panel, the headlight relay should have a blue wire running to the connection at the 3 o'clock and the 6 o'clock positions (viewing the relay connections as a clock; looking down on the panel with the top of the panel pointing towards you). The blue wire runs to 3 o'clock (the control input) first, then down to the 6 o'clock (power input) position. It originates from the relay to the immediate right (the 12 o'clock position). The entire wire runs to four different places (it has four connectors on it).

Flip the panel back up to the vertical position. Remove the headlight relay. Each spade connection fits into the panel in a slot with a small hole or notch on one side. Stick an awl or a thin bladed screwdriver into the small hole as far as you can (about 1/4 to 3/8 of an inch). This releases the locking tab for the wire connector on the back of the panel. From the back of the panel, pull the blue wire out of both the 3 o'clock and the 6 o'clock positions.

Using wire cutters, cut the blue wire so that there is just one connector. Cut it at the 3 o'clock connector so that the wire no longer continues to the 6 o'clock connector. Save the connector and short wire that used to run to the 6 o'clock position.

Insert the remaining connector on the blue wire into the 6 o'clock (power input) position. You should now have a wire running from the 6 o'clock (power input) position on the headlight relay directly over to the 12 o'clock position on the relay to the right. The 3 o'clock (control input) position should be empty.

Add a new control circuit. Use a pair of 200 volt/1 amp diodes in a Y configuration, where the branches of the Y connect to the bottom spade connections for the #10 and #12 fuses, and the trunk of the Y connects to the 3 o'clock (control input) position on the relay. The current must flow FROM the fuses TO the relay control input, otherwise you will blow the fuses. Use the connector and the short length of blue wire you cut off previously, inserting the connector in the 3 o'clock position in the relay panel. Be careful, of course, to make sure nothing will short to anything once it is all put back together. You can cover the diodes and their exposed leads with the heat shrink tubing. If the tubing shrinks too much lengthwise, use a little electrical tape to ensure that everything is adequately insulated.
Wiring the relays in this manner will activate the headlight lifting motors whenever either the left headlight low or high beam is on. You could also connect to fuses #11 and #13. In either case, the motors will now only activate when the headlights are switched on.

Replace the relay, relay panel, and fascia cover.

Test your work.

How the Circuit Works
One relay controls whether the headlight lifting motors are activated. It has one power input, two power outputs (switched), a control input to the solenoid, and a ground for the solenoid. The stock wiring is for power to be applied to both the control and power input at the same time by the light switch on the steering column moving to either the park or headlight position. In addition, the light switch applies power to the headlight bulbs themselves whenever it is moved to the headlight position.

The above modification changes this so that the light switch only applies power to the power input when it is in either the parking lights or headlights position. The control input is driven by power being applied to either the high or low beam bulbs themselves. As a result, the solenoid making the headlights lift is only activated when the headlights are actually on.
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