Strange Headlight/Turn Signal Interaction

[OsoMoore]

I've noticed a funny issues recently when driving at night.

I'll be driving along with my normal headlights - not brights. If I wiggle the stalk around, there is nothing funny - my brights don't flicker on unless I click it into position.
However, if I turn on my right turn signal, and then make a turn and let it click off as I straighten out, my brights will come on in addition to my normal beams. Then a gentle poke of the stalk will turn the brights back off, leaving me with my normal beams.

This only occurs when I turn right - not left.

I suspect I ought to replace the stalk, as its old and brittle. However I'm not sure its worth the cost until something actually breaks.

[yazhound]

Had basically same phenom on my 88 Carrera. Stalk was shorting out. It got to point where left signal not work with the lights on.... right was fine...

[porwolf]

Common problem, happens to all of us eventually. There have been quite a few threads on the forum, for instance:

turn signal switch quick fix pictures

[OsoMoore]

Hmmm, if its shorting out then perhaps it is an issue which could lead to inoperable lights or blinkers. I should probably fix it.

EDIT: Holy moley the linked thread is awesome! I can't believe this is so common.

[darrin]

Originally Posted by OsoMoore

Hmmm, if its shorting out then perhaps it is an issue which could lead to inoperable lights or blinkers. I should probably fix it.

Agreed -- seems the root cause of this is that, in its infinite wisdom, porsche runs the headlights' full current through the turn signal switch -- this creates heat that causes/speeds up the distortion that creates the problem.

Our host sells a headlight relay kit that solves this problem by keeping the headlight current away from the turn signal switch -- probably a good simultaneous upgrade to perform.

[tirwin]

Have you installed the headlight relays? You will just fry the stalk again if you replace it w/o adding the relays. Ask me how I know...

[OsoMoore]

I'm new to my car. Is there an easy way to tell if you already have the headlight relay installed?

[tirwin]

Originally Posted by OsoMoore

I'm new to my car. Is there an easy way to tell if you already have the headlight relay installed?

I'm not where I can take a picture, but if you look at the front fuse panel, the relays are typically two squarish boxes attached to the bottom right corner of the fuse panel. If you search on the Pelican store for headlight relay you will find a picture. You can also search in the forum. Look for user JWest as he's the one that sells them through our host. This is pretty common.

It's not a bad job and well worth the investment. This is one thing Porsche engineering did not get right -- the power for the headlights normally runs through the turn signal stalk which reduces their lifespan. The relays are cheap insurance.

[CCM911]

I just sprayed a bunch of electrical contact cleaner in mine and then worked it up and down, forward and backwards. Problem solved. It could just be dirt.

Mine would put on the high-beams every time I made a turn using the signal. As soon as the stalk would re-center, the high beams would come on.

You are lucky. A common problem with known solutions.

Have fun!

[OsoMoore]

I need to figure out how to remove the assembly - I have an aftermarket wheel. I'll figure it out and post pics.

[HarryD]

To remove the stalk, you will need to:

1-Disconnect battery;
2-Remove the horn button (post a shot of your steering wheel to help tell you how to do this);
3-Remove the steering wheel by removing the 27 mm nut holding the steering wheel to the the steering shaft. Be sure your steering lock is disengaged (key in accessory position). Use something to keep the steering wheel from turning.;
4-Remove switch.
5-Installation is reverse of above.

[tirwin]

Just to add to what Harry said, the main thing you want to avoid when taking off the 27mm nut is putting too much force against the rack and pinion. One way some people have done it is to use The Club (yes the security device) on the steering wheel to provide resistance against your ratchet hand. A perhaps better way is to use a 1/2" impact wrench. This project is covered in the 101 Projects book our host Wayne wrote.

[OsoMoore]

Originally Posted by tirwin

Just to add to what Harry said, the main thing you want to avoid when taking off the 27mm nut is putting too much force against the rack and pinion. One way some people have done it is to use The Club (yes the security device) on the steering wheel to provide resistance against your ratchet hand. A perhaps better way is to use a 1/2" impact wrench. This project is covered in the 101 Projects book our host Wayne wrote.

I pulled out my trusty copy last night and indeed read all about it. I don't have a club, or an impact wrench, so I didn't attempt to get the bolt off. I did, however, have fun taking the rest of the wheel assembly apart and putting it back together. I honked the horn a lot too! I should have DC'ed the battery...

I'll see if I can find someone to borrow the wrench from, but with only 2 evenings until we drive to Canada I'm not sure I'll be able to get it done. I did try some contact cleaner spray to no avail.

[OsoMoore]

I got an impact wrench and did the deed last night. I don't recommend reassembling the wheel in the dark! I made a small shim to separate the contacts, and poked at the "flash" contacts until they were usable again.
I don't know how long the shim will last, but now that I know how it all goes together it will be fast if I need to fix it again.

I also found the left stack assembly screws were loose - after tightening them the whole thing feels a lot better.