Ferrari 365/400/412 "Sleepy" Headlight

Hello,

I am starting to use the 412 as a "daily", and this has happened to me a few times.

It is an intermittent issue, which makes the diagnosis a bit more challenging.

I was able to use the manual knob underneath the rubber cover, but I would like to get this repaired.

I recall reading that the issue could be with the "tracks" of the closing mechanism?

Has anyone had this issue and knows how it has to be addressed?
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Open the motors (removing the rubber boot is the hard part), clean the grease on the tracks, while you are there, clean also relube the worm gear, check the 2 diodes (that's useless on the 400, but everybody will tell you to check them as they get burnt in the other Ferraris). Reassemble, and call it a day.

See https://www.ferrarichat.com/forum/threads/funky-headlight-behavior.630548/#post-147528843

 

This can be related to the relays...swap the light relays with other ones of your fuse board.

 

Thank you - will take a look.

 

Take Guido's advice and replace the relays before you do anything else. These types of problems are almost always related to the relays, go there first. It's easy and cheap.
Alden

 

Yes could be, but "incidental": the stock relay coil does consume 200mah, so the lifting motor track and diodes have to be in pretty good shape in order to provide enough juice just to trigger the relay coil. The new bosch relay (plastic case) is less power hungry so can make it do with a less conductive feedback mechanism.

This being said, it's easy to swap the right and left relay (as long as you remove all the floor and quite some bits of leather trim to access the panel...)

 

Great - thanks. Do you happen to know the Bosch relay prt number?

 

The relay panel and its ref is in the owner manual (at least it is in the 400i manual), thne you can source alternative relays based on this explanation I wrote a while back. Be carefull no to buy relays that cure nack emf with a diode as ferrari reversed the polarity of some coils.

https://www.ferrarichat.com/forum/threads/a-c-woes.626912/#post-147446406

Aside from the "K"/blue relay all are easy to source/substitute. Genuine relays are available through Autodoc (German based). Having at least a couple of each is a good idea.

 

By the way I never had a Bosch relay failed!

Once you open the metal casing it's easy to clean the old lubricant and they will work better than new. The contacts are really beefy and hardly fail. In fact the surface area gets even better after a few hours, hence the reason why old ones do have a lower internal resistance than shiny new ones.

Their only issue is related to their proximity with the exhaust manifold that "cooks" the lubricant.

The latest design (plastic casing) are of high quality, but not serviceable unfortunately.