Dim Low Beams

[kcope]

Hi All
When I first purchased my 911 in May I noticed that my low beams were very dim (H1s) but the high beams were fine. I swapped with headlights from one of my Triumphs that I knew worked fine. Same problem, highs fine, lows suck. So I bought the
H4 set up. Yup you guessed it, Highs fine, lows a tiny bit better but still unacceptable. At least now I can see the where the low beams hit the road.
Where should I start? I have already cleaned and tightened the ground connections even though I know that's not the problem. I also plan to install relays on both high and low beams over the winter.
Any assistance would be much appreciated.
TIA

[scottb]

I had a similar problem years ago with another (non-Porsche) car. I found that the ground to the headlights wasn't sufficient or had degraded. It's possible you have a bad ground cable, so you might consider replacing that. I ended up adding a separate ground wire to the dim headlight on my car, and it solved the problem.

Good luck.

[Argo]

A few quick thoughts - does the high beam indicator light in the dash work correctly (lit up brightly when the highs are on; completely off when the highs are off)? When I first put my H4's in I had the wires on incorrectly; the highs were great, the lows were very dim and the indicator light was always on (either brightly or dimly). If I remember correctly, with the tabs on the light forming an inverted U, the left one was ground, the top was low and the right was high. I remember a recent post here with a picture that can confirm this. Just a longshot guess - if you have that many Triumphs you by now no doubt have a strong background in auto electrics (I have a 74 Spitfire myself).

The stalk switch for high/low/turn indicators is also a usual suspect for problems.

Argo
88 Targa

[derek murray]

H4 below; terminal # 1 - earth (brown), #2 - low (yellow), #3 - high (white)

[Argo]

Yup, that's the one.

Argo
88 Targa

[hilandscott]

It's possible you have a bad ground cable, so you might consider replacing that.

Would this be near the bumper or inside the headlight bucket?

[kcope]

Hummmmmmm I think that it wouldn't hurt to check the battery ground. the headlight grounds are seperate so a bad ground would only affect one side.
It also looks like I might have the wiring wrong (see pic) but I don't get a high beam light on low and it would seem like my beams would be reversed. I'll switch that too and see what happens.
As you can see I didn't have any plugs when I bought the car I have since put plugs on.
Any other ideas?

[kcope]

oops heres the pic

[scottb]

Lotta gunk in there. I'd take it apart and clean the contacts with some emory cloth and/or a small file. I think it's a good place to start, at least.

[Determined]

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[lindy 911]

I'm having a similar problem. I'm thinking of adding electrically held contactors that are controlled by the original headlight wiring but adding direct wiring from the main 12 volt buss to the headlights direct. I'm sure this has already been done.

Lindy

[Trackrash]

I had the same problem.

Check you fuse block. Check if your lowbeam fuses are hot.

The problem on my car was the riveted connector on the back of the fuse block had a small amount of corrosion and thus resistance. The heat just about destroyed the fuse block.

I had to solder the rivet to ensure a good electrical connection AND add a RELAY.

[sballard]

Your wiring doesn't match the image. Could this be the cause?

[FastCarFan]

I have always thought that my headlights - both low & high - beams are marginal at best. A couple years ago I had a problem with my low/high beam switch & my high beams were on regardless of stalk position. What's funny is no one noticed!

My commute involves mostly 2-lane highways & at that time of year (fall) I had the headlights on both driving to & from work. I drove the 911 for 3 or so days & not one person flashed their lights at me because my high beams were on!

[HarryD]

Doug:


Sound like you turn /hi beam control switchis bad. Check this thread (turn signal switch quick fix pictures) for a DIY fix or replace it. You should also add headlight control relays to protect the turn signal/hi beam switch.

[lindy 911]

I just went out and looked at my wiring and it was just like Kens image. I changed it to the H4 picture and it's a lot better. Both high and low have the same intensity.

Lindy

[DRACO A5OG]

Contact Daniel Stern.

I have the H1's and his bulbs, literally day and night compared to anything on the market.

Here is my thread: Daniel Stern Review

I have literally tried everything short of going HID: Sylvania Silver Stars, PIAA's, 100Watts ... None compare to Daniel's Bulbs. In fact I moved the left over Silver Stars and PIAA bulbs over to the Hi-Beam's, the lo-beams are much brighter.

No affiliation to Daniel Stern.

[FastCarFan]

Originally Posted by HarryD

Doug:


Sound like you turn /hi beam control switchis bad. Check this thread (turn signal switch quick fix pictures) for a DIY fix or replace it. You should also add headlight control relays to protect the turn signal/hi beam switch.

Thanks, but it was fixed a year or so ago. That is exactly what the problem was.

[HarryD]

Originally Posted by FastCarFan

Thanks, but it was fixed a year or so ago. That is exactly what the problem was.

Sorry, thought you were describing a current problem.

[RSBob]

Sounds like you are low on electricity. I would buy a 12 oz bottle of 12 V ZAP at Napa and add to your electrical system.

After you are done, (finding a legit solution) please post your results.