‘87 High Beam issue

[Terrafirma]

When I turn on the high beams my headlights turn off. Where should I start to diagnose this issue?

[Joe Bob]

Turn signal stalk.

[darrin]

Originally Posted by Terrafirma

When I turn on the high beams my headlights turn off. Where should I start to diagnose this issue?

high beams are separately fused from low beams -- start by checking their fuse (and swapping with low beam just to be sure). Do high beams work if you pull the stalk to flash them?

[pavegeno]

AFter a few turn signal stalk changes and trying to extend the life of the stalk by spreading the metal contacts, I purchased and had installed The Classic Retrofit fuse holders (front and back) that incorporate a relay for the headlights/turn signals which takes the load off the turn signal stalk.

https://www.classicretrofit.com/en-us/collections/blade-fuse-panels/products/911-front-fuse-panel-1974-1989

[Terrafirma]

Originally Posted by darrin

high beams are separately fused from low beams -- start by checking their fuse (and swapping with low beam just to be sure). Do high beams work if you pull the stalk to flash them?

They do not flash if I pull the stalk. They completely turn off when I push forwards on the stalk to engage high beams.

[darrin]

Originally Posted by Terrafirma

They do not flash if I pull the stalk. They completely turn off when I push forwards on the stalk to engage high beams.

if your high beam fuses are OK, I'd concur that your next step is to check out and repair/replace the turn signal stalk. Also concur with pavegno's advice regarding headlight relays. You can add relays without replacing your fuse box -- our host sells this easy-to-install set -- https://www.pelicanparts.com/More_Info/JWST911HLPR.htm?pn=JWST-911-HLPR&bc=c&SVSVSI=

[pavegeno]

Originally Posted by darrin

if your high beam fuses are OK, I'd concur that your next step is to check out and repair/replace the turn signal stalk. Also concur with pavegno's advice regarding headlight relays. You can add relays without replacing your fuse box -- our host sells this easy-to-install set -- https://www.pelicanparts.com/More_Info/JWST911HLPR.htm?pn=JWST-911-HLPR&bc=c&SVSVSI=

That looks like a great relay kit and for a great price!

I had previously upgraded my alternator to the Classic Retrofit 175A alternator due to voltage drops with all the electrical load with four condenser fans and hurricane air conditioner blower fan from Griffith's. I was so impressed with it that I decided to replace the fuse blocks, front and rear, with the CR kit to keep modernizing the car for long life in a stealthy manner. I retained the original fuse blocks.

[winglesss]

That Pelican Parts / JWEST Engineering headlight relay kit is a great upgrade at a great price.

The only thing I don't like in the instructions is tapping off power by adding another wire to the battery terminal and would instead prefer it to be connected onto a different high current location.

My choice for this upgrade was instead to use those round Porsche relays, populated into the two empty relay locations, for an OEM appearance, unfortunately at a much higher cost.

[Terrafirma]

The relay did not fix my issue.

[winglesss]

Welcome to the forum.

The Bentley Publications wiring diagram for your 1987 911 has been studied and it doesn't make any sense.

The OEM Porsche Factory Service Manual set was ordered over a month ago and is expected in several weeks. It sounds like it is coming from Germany.

When it arrives I will again examine the headlight schematic to see if better information may be provided.

Use low beams until then...