Pop up Head lights go up and down when turned off

[MaSnaka]

My head lights seem fine except when I shut them down. They will continue going up and down repeatedly 5-10 times before they stop. Not the lights but the cups open and close on their own. Any ideas what to look at??
Thanks,
John

[curtisr]

This reminds me of when I accidently installed a four-way flasher relay (which looked identical) in place of the headlight relay in my '82 928. Simply put, I'd test the headlight motor and the headlights relay.

[originalowner]

The relay mounted on the headlight lifting motor is suspect.

[Jfrahm]

That or the rotary contacts in the headlight motor assembly. These can be cleaned.

[Monkey Wrench]

Originally Posted by curtisr

This reminds me of when I put a four-way flasher relay (which looked identical to the one for the headlights) in my '82 928. Simply put, I'd test the headlight motor and the headlights relay.

way OT but..
had a workmate that liked to play practical jokes so one day I got him back...

I crawled under his car and connected his headlights to his horn.. signal lights would have been funnier. but didn't want to cut or damage his wiring.

I used a big fat red wire so that I figured when he opened his hood he could figure it out straight away... lol


he came in the next day, no reaction, so I said "oh I guess you dint go out last night".. lol.. he just gave me a quizzical look.


i tkind of backfired, next night he got in after drinking a few beer, started the car turned on the headlights all in one go.. and then couldn't shut his horn off ;-) the beer probably didnt help..

I had figured he'd find it as soon as he turned his lights on, it was a junky old dodge dart.. we laughed about it later.. - kids lol..

,,,
agree with the above on the headlight up and down issue.

[originalowner]

Originally Posted by Jfrahm

That or the rotary contacts in the headlight motor assembly. These can be cleaned.

I thought I's start him on the easier check first.

[Dano944]

I replaced the relay on the headlight motor which seemed to help. Then it started flipping again. I cleaned the contacts on the relay wires and so far it’s been good. But the other day, the lights got stuck halfway, which closed when I flipped off the lights. I think after 40 years, the mechanics of this archaic headlight mechanism are just tired. I found the more I use them, the less problems I get.

[originalowner]

Sorry the easy fix didn't do it. Next up...

https://www.clarks-garage.com/shop-manual/elect-21.htm

[curtisr]

Testing the printed circuit board diode ( + --|>-- setting) with the red probe on the cathode side (-'ve) -- with the stripe -- to check for a voltage drop of about 0.5V -- 0.7V. Reverse the probes:

• Good diode: Shows a voltage drop in one direction and OL or 1 in the other.
• Bad diode (shorted): Shows a voltage reading in both directions.
• Bad diode (open): Shows OL or 1 in both directions.

A new diode is less than $20 from the usual suspects. Part Number: 477941383

Here are a couple of other possibilities:

[MaSnaka]

Thanks for the responses guys. I will look into it but maybe its from a lack of use. The car doesnt get driven daily and rarely in the dark.
John

[originalowner]

Ground wire is another possibility. The motor grounds through the casing, but the relay grounds through the brown wire.

[porschemech]

Shake connector on motor by relay, these get loose and wear out.
944online sells new ones.
Good luck

[Monkey Wrench]

I think the motor needs to be electrified to move and you can't normally electrify somethign inadvertently by a bad contact or ground. If its not a relay issue probably the contact wheel thing is dirty.
it sounds like a fight with the aged rubber. Id set it in extra soapy hot, near boiling water for a while, that will probably make it easier to work into place without tearing the rubber. just don't captivate any water by doing so.

probably good to disconnect the battery as if that thing catches your hand its geared down, might cause injury if it moves unexpectedly.

ive seen instances where people working alone get their hand stuck, in a machine. it can be a terrifying situation to get back out of.

my dad once jacked a car with a fatory jack, the car rolled and pinched him, good thing mom knew how to work a car jack. he had stick a spare tire unde rth ecar, he still broke some ribs. I tend to add extra blocks just to keep safe.

I was lying under a car wrencihg away and put my hand on a rocker panel to brace myself. a strong gust of wind blew the car door closed. trapped my fingers. I managed to pull them free. certainly unexpected.

a friened working nights alone on a printing press fed his fingers in the the rollers so he was standing there hurting and he could reach the controls to inch the machine either way, Now which way would pull his hand in deeper and which way would bcak him out? that was immediately confusing. He was very thankful that he won the 50 50 chance .