Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

Tail lamp warning?

Thread Tools
 
Search this Thread
 
Old Feb 4, 2005 | 12:30 AM
  #16  
Bill Ball's Avatar
Bill Ball
Under the Lift
Lifetime Rennlist
Member
20 Year Member
 
Joined: Mar 2002
Posts: 18,648
Likes: 52
From: Buckeye, AZ
Default

Originally Posted by SilverSFR
If anyone needs a Bulb controller out of a 1982 (works great) I have an extra. Its the result of an educated guess to solve my tail lamp warrning. It wasn't the bulb controller. 45.00

SilverSFR
Yeah, like the time my A/C stopped working and I surmised it was probably that underspec'd relay. Carefully unsoldered the original and spliced in the heavy duty replacement. Uh, no-go. Should have checked the freon first. Doh!
Reply
Old Feb 4, 2005 | 12:39 AM
  #17  
V-Fib's Avatar
V-Fib
We had a choice?
Rennlist Member
20 Year Member
 
Joined: Feb 2002
Posts: 18,952
Likes: 459
From: Texas
Default

My errant and persistent light was caused by the lamp controller. The inside was badly corroded. It was the last thing i checked/replaced after going through all the light connections, wiring and bulbs 3 times.
Reply
Old Feb 4, 2005 | 01:20 AM
  #18  
SharkSkin's Avatar
SharkSkin
Rennlist Member
 
Joined: Jan 2004
Posts: 12,620
Likes: 8
From: Boulder Creek, CA
Default

Originally Posted by Bill Ball
Yeah, like the time my A/C stopped working and I surmised it was probably that underspec'd relay. Carefully unsoldered the original and spliced in the heavy duty replacement. Uh, no-go. Should have checked the freon first. Doh!
I almost did that too. The problem kept nagging at me and it took two more spelunking trips with the multimeter(trying to prove to myself that the head unit WAS the problem) before I realized that the problem was actually an open circuit in the fuse panel itself.
Reply
Old Feb 4, 2005 | 03:14 PM
  #19  
IcemanG17's Avatar
IcemanG17
Thread Starter
Race Director
 
Joined: Sep 2004
Posts: 16,271
Likes: 82
From: Stockton, CA
Default

I will have to check the side markers and license plate lights? Hopefully its one of those! Luckily for my friend he is not a perfectionist like me, so he can live with an annoying warning light that would drive me crazy!

Perry
Sounds like you have a very annoying gremlin in your system somewhere. Maybe you should try pulling the pod and cleaning the connections? I heard this causes odd warning lights sometimes?
Reply
Old Feb 4, 2005 | 10:59 PM
  #20  
John Struthers's Avatar
John Struthers
User
 
Joined: Jul 2001
Posts: 3,291
Likes: 2
From: Midland, Texas
Default

My light switch came in from 928 INTL about a week ago.
I've done EVERYTHING else, and am hoping this resolves this warn problem.
Will swap it out tomorrow.
Black tape is currently residing over the taillight warn and master caution.
Reply
Old Feb 4, 2005 | 11:02 PM
  #21  
John Struthers's Avatar
John Struthers
User
 
Joined: Jul 2001
Posts: 3,291
Likes: 2
From: Midland, Texas
Default

Oh Yeah!
SilverSFR,
Someone should snap up that used LCU ... that's a damn good price!
I replaced mine as well ...same result...nada.
Reply
Old Feb 4, 2005 | 11:39 PM
  #22  
SharkSkin's Avatar
SharkSkin
Rennlist Member
 
Joined: Jan 2004
Posts: 12,620
Likes: 8
From: Boulder Creek, CA
Default

John -- EVERYTHING else?
Reply
Old Feb 4, 2005 | 11:48 PM
  #23  
snoz's Avatar
snoz
Addict extrordinare
Rennlist Member
20 Year Member
 
Joined: Dec 2004
Posts: 686
Likes: 70
From: Kansas City, MO
Default

Mine did that for the first time tonight after going through the car wash. It comes on immediately after starting the car and turning on the lights. It goes off after about a minute of driving. I'm guessing I got a wet socket.
Reply
Rennlist Stories

The Best Porsche Posts for Porsche Enthusiasts

story-0

Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture

 Verdad Gallardo
story-1

Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look

 Verdad Gallardo
story-2

10 Porsche Colors That Have More Personality Than Most People

 Verdad Gallardo
story-3

Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod

 Verdad Gallardo
story-4

10 Reasons I Hate Going to the Porsche Dealership (& the 1 Reason I Stay)

 Joe Kucinski
story-5

Porsche Shakes Up The Nürburgring Lap Record Table Once Again

 Verdad Gallardo
story-6

6 Ways the Porsche 911 GT3 S/C Redefines Performance

 Joe Kucinski
story-7

10 Wildest Homologation Specials Porsche Ever Sold

 Verdad Gallardo
story-8

Super Rare RUF BTR III Comes Out of Hibernation, Looking For a New Home

 Verdad Gallardo
story-9

10 Porsche Opinions That Can Start a Fight

 Joe Kucinski
Old Feb 5, 2005 | 12:17 AM
  #24  
WallyP's Avatar
WallyP

Rennlist Member
Rennlist Site Sponsor

20 Year Member
 
Joined: Jun 2001
Posts: 6,469
Likes: 13
From: Ball Ground, GA
Default

There were a few mis-statements in this thread...

The "Tail Light" warning and the "Brake Light" warning are very different.

The normal action for the "Brake Light" warning is for the warning to be on after the engine is cranked until the brake pedal is pressed. If the bulbs are good, the warning then goes off. The only bulbs that affect this warning are the brake lights in the tail lamp housing and the CHMSL (Center High Mounted Stop Lamp).

The "Tail Lamp" warning can be affected by the tail lamps, side marker lamps and license plate lamps. This warning may come on at any time after the parking lamps (or head lamps) are turned on.

The Bulb Check Unit is located between the glove box and firewall on most cars. It is different from the Central Warning Computer, which is located in the dead pedal in most cars.
Reply
Old Feb 5, 2005 | 01:21 AM
  #25  
perrys4's Avatar
perrys4
The Lady's Man
Rennlist Member
 
Joined: Sep 2003
Posts: 10,444
Likes: 1
From: south O.C. california
Default

Wally, in my case, which one, the bulb check unit or the central warning computer is most likely to be my culprit.
Reply
Old Feb 5, 2005 | 01:23 AM
  #26  
Bill Ball's Avatar
Bill Ball
Under the Lift
Lifetime Rennlist
Member
20 Year Member
 
Joined: Mar 2002
Posts: 18,648
Likes: 52
From: Buckeye, AZ
Default

Originally Posted by WallyP
The Bulb Check Unit is located between the glove box and firewall on most cars.
Thanks for the corrections, Wally. Isn't the lamp control (bulb check) unit below and to the sidewall side of the glovebox (above the LH brain on later models)? I think it's mounted on the end of the passenger package tray in my 89. The box between the glovebox and firewall (i.e., behind the glovebox) on my car is the alarm control unit. The central warning controller is under the dead pedal, as you said. It still may be involved in false bulb warnings, as I recall.
Reply
Old Feb 5, 2005 | 02:42 AM
  #27  
SharkSkin's Avatar
SharkSkin
Rennlist Member
 
Joined: Jan 2004
Posts: 12,620
Likes: 8
From: Boulder Creek, CA
Default

I went round and round with this when I first got my car. It turns out(at least on my 78, and allegedly on all sharks) that the front parking lights in the bumper can cause a tail lamp warning. The problem went away when I replaced those two and cleaned up the sockets and connectors.
Reply
Old Jun 23, 2005 | 01:04 PM
  #28  
_Thomas_'s Avatar
_Thomas_
Advanced
20 Year Member
 
Joined: May 2003
Posts: 68
Likes: 8
From: Switzerland
Default

Hi on my '84 S2 I had a problem with a working/non-working tail lamp for a long time. I tried to clean the contacts of the bulb several times, also cleaned the 9pin-connector inside (next to rear fenders, hidden under the interior panel). I did measure a voltage on the bulb contact, but not a very stable one.
The problem was an unstable contact in the light control unit (bulb tester). The light control unit is screwed to the lower compartment on the passenger side and can be opened easily (4 little screws hold the housing together). There are no mechanical parts or relays inside, just relatively big coils and resistors.

Save the 200 $ for a new light control unit, it can be repaired by re-soldering everything on the print and also soldering the contacts to the print, which are pressed together.
Cheers Thomas
Reply
Old Jun 23, 2005 | 01:25 PM
  #29  
deliriousga's Avatar
deliriousga
Three Wheelin'
 
Joined: Oct 2004
Posts: 1,407
Likes: 0
From: USA!!!
Default

A similar problem in mine last week was a broken wire in the hatch. Since the tool kit pushes down on those wires, one of them had rubbed the metal clip that holds the harness and cut it in half. Something to look for if you get the "tail light" warning.
Reply
Old Jun 23, 2005 | 01:28 PM
  #30  
GregBBRD's Avatar
GregBBRD
Former Vendor
 
Joined: Feb 2005
Posts: 15,228
Likes: 2,529
From: Anaheim
Default

The bulb contoller will set off the warning light if it detects increased resistance from one side of the car in comparison to the other side. So, all the lights can work visually, but if there is corrosion on one of the sockets, or bulbs, the warning light can still light. This frustrated us, too, until we fiqured it out. Pretty much need to clean all the sockets and replace all the bulbs (clearance, taillights, and license.) Make sure the bulbs are all rated correctly. We've had cars where a different amperage bulb was installed in one socket. Of course the computer detects this as increased resistance and sets off the warning light. Again, hard to detect, since all the bulbs light.
Reply



All times are GMT -3. The time now is 11:18 PM.

story-0
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture

Slideshow: Porsche has created a Japan-only 911 GT3 Artisan Edition that blends track-ready hardware with design cues inspired by traditional Japanese craftsmanship.

By Verdad Gallardo | 2026-04-28 19:00:17


VIEW MORE
story-1
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look

Slideshow: Porsche's latest electric Cayenne Coupe blends dramatic styling with supercar acceleration, turning the brand's midsize SUV into a 1,139-horsepower flagship.

By Verdad Gallardo | 2026-04-27 19:39:30


VIEW MORE
story-2
10 Porsche Colors That Have More Personality Than Most People

Slideshow: Porsche's wildest paint colors aren't just shades-they're full-blown personalities on four wheels.

By Verdad Gallardo | 2026-04-27 19:38:13


VIEW MORE
story-3
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod

Slideshow: The last of the Speedsters doesn't just close a chapter, it makes quite the bold, air-cooled statement.

By Verdad Gallardo | 2026-04-22 17:55:04


VIEW MORE
story-4
10 Reasons I Hate Going to the Porsche Dealership (& the 1 Reason I Stay)

Slideshow: Going to a Porsche dealership may not be the dream experience you expect it to be and these are the reasons why.

By Joe Kucinski | 2026-04-21 13:54:19


VIEW MORE
story-5
Porsche Shakes Up The Nürburgring Lap Record Table Once Again

Slideshow: Porsche just proved-again-that precision engineering can outrun brute force at the Nürburgring.

By Verdad Gallardo | 2026-04-18 20:27:02


VIEW MORE
story-6
6 Ways the Porsche 911 GT3 S/C Redefines Performance

Slideshow: Six reasons why you will love the Porsche 911 GT3 S/C and 1 reason you will hate it.

By Joe Kucinski | 2026-04-14 10:21:39


VIEW MORE
story-7
10 Wildest Homologation Specials Porsche Ever Sold

Slideshow: Some of the most desirable Porsche models are those that were sold to the public solely for homologation purposes.

By Verdad Gallardo | 2026-04-08 09:54:26


VIEW MORE
story-8
Super Rare RUF BTR III Comes Out of Hibernation, Looking For a New Home

Slideshow: The lone BTR III-spec Targa features rare RUF engineering with a 430-hp turbo flat-six and fewer than 30 miles since its rebuild.

By Verdad Gallardo | 2026-04-06 20:03:25


VIEW MORE
story-9
10 Porsche Opinions That Can Start a Fight

Slideshow: If you want to start a debate with a Porsche friend, these 10 opinions are a great way to get started.

By Joe Kucinski | 2026-04-02 16:53:02


VIEW MORE