Grand Prix headlight strength

I use the Silverstars on my Bonneville. I get a whiter beam, but not necessarily brighter. And I know what you mean by weak illumination, it seems I have a similar problem.

-- markwb

2001 Bonneville SLE

equivalent)

The SilverStar's are brighter and whiter in our 00 GP, not a huge difference but definitely better. I have heard, however, that the longevity is greatly reduced over the stock lights (ie, since they are always-on they may last only 1yr but of course that depends on how long the vehicle is on - I have SS's on another vehicle that also has DRL's, so far on it they have lasted >1yr).

Oh, that's too bad. I think what the problem would be is that the GP's (and I assume the same is true for the Bonneville, and possibly other Pontiacs too), is that their lens is clear and there is no internal reflection going on. In other lens with the internal ridging, I guess the light has a chance to reflect backwards to the back reflectors where they bounce around a little to spread the light around the entire surface of the lens.

Yousuf Khan

Hmm, yes, I can imagine that the SS's are lower longevity, since they run much hotter. I bought a bunch of them for my brother-in-law's Corolla as a present, but he hasn't installed them yet, so I don't know how they fair.

Yousuf Khan

One other problem I had with Silverstars is the 880ST's that I bought for my driving/fog lights is they only lasted two months. I'm back to the conventional 880 halogens.

-- markwb

2001 Bonneville SLE

This is a well-known problem with both the 97-03 GP's and from what I'm hearing it wasn't fixed with the '04 redesign either.

Here's what I did for my 2000 GTP:

- Replaced headlight bulbs with 9007 Sylvania Silverstars

- Installed upgraded headlight wiring harness

Replaced fog lamp bulbs with 880 Sylvania Silverstars- Modified wiring to re-route daytime running lights to fog lights ratherthan headlights to help 9007 Silverstars last longer Or you can justdisable DRL's altogether All these changes did make a noticeable difference in the amount/quality of light when driving at night.

There's a guy who is putting together HID kits for the 97-03 GP and it's gotten good reviews but it's quite pricey

All of this info came from the forums as This is a great site with a lot of info on the Grand Prix.

Hope this helps.

Scott

Why is this necessary? Don't the Silverstars work as drop-in replacements for existing halogen lamps?

Interesting idea.

Yousuf Khan

It's not necessary. The Silverstars will work with the factory wiring as drop in replacements. Using a wiring harness upgrade of this type will improve headlight performance/reliability by giving a better, more direct connection to the battery. The harness upgrade allows headlight bulb current to bypass the (flimsy) headlight switch contacts in the steering column switch and the rest of the associated contacts between the battery, steering column and headlight bulbs.

With the wiring harness mod, the factory switch in the steering column controls the relatively low current needed to operate the relay in the upgraded harness, while the new relay handles the relatively high current drawn by the headlamps.

I did a similar mod to my high mileage GA after the headlight switch crapped out.

Were you able to try the Silverstars before and after the harness mod? If so, did you see a difference?

Yousuf Khan

I considered, but never tried the Silverstars. I had and still have OEM type bulbs. In my case, I had defective wiring. The wiring harness connector at the steering column headlight switch had overheated causing poor electrical contact. Also, the headlight switch itself was broken (pulling on the stalk to turn on the high beams didn't work - the switch wouldn't lock in the high beam position).

I replaced the switch, and cleaned up the contacts in the overheated connector at the column. I installed relays near the battery to handle the bulb current and the headlights are brighter than ever.

My "brighter than ever" observation may be biased. It's a twelve year old GA and the headlights were probably getting dimmer and dimmer very slowly over a period of years.

To tell if it would make a difference in you car, you could use a voltmeter to measure the battery voltage (engine running, lights on). Measure the voltage at the headlight bulb connector(s) and compare the two. If you see lower voltage at the bulb socket, a wiring harness mod might make an improvement. If the difference in voltage were less than half a volt, I'd guess that everything is in good shape and the wiring harness mod wouldn't make any difference in the intensity of the headlamp light.

Dave

Okay thanks, at least now I know the history of your car and whether it applies to mine. Since my car is a few years younger than yours, and I haven't experienced any overheated wiring harnesses yet, I'll probably just try out Silverstars one of these days.

Yousuf Khan

Yes, they work fine as drop-in replacements. The upgraded harness slightly increases the voltage that the bulbs get making them even brighter than if you just plugged them into the existing wiring.

Of course the increased voltage probably decreases their lifetime but mine have been running for >6mos now with no issues.

Scott