Scott in Tampa writes:
Hey Guys, this problem (in my 2001 Saturn) occurred first when I was driving at night and and my dash illumination went dark! I had probably blown a fuse. Yes, it was a 10AMP mini fuse labeled BRAKE LP in the engine fuse compartment. Does LP stand for “Lamp”? I believe the dash illumination went out as a warning for what was really wrong – the running tail lights (constant lights) on the back of my car were out!! Now, when I press on the brake, the bright brake/tail lights still respond. It is only when I turn on my running lights that I get NO lights in the back of my vehicle.
Another observation: When this originally happened, I replaced the fuse. It lasted about a week before it tripped again. Replaced that fuse, it lasted a few days. Now, the fuse blows within seconds of inserting a new one. Sounds to me like a wire may be short circuiting somewhere?? What is the likelihood that this wiring is bad near the engine opposed to back trunk location?? Any insight or help would be greatly appreciated.
Sajeev replies:
You’re on the right track, but you’re also over thinking the situation. The Saturn L-series has a recall related to your problem. (If you have an L-series, that is.) While we may never know why recalls/TSBs always come in ALL CAPS, here’s the unfiltered advice:
“ON CERTAIN SEDANS AND WAGONS, THE PLASTIC HOUSING IN THE REAR TAIL LAMP ASSEMBLY CAN BECOME DISTORTED IF THE BRAKE LAMPS REMAIN ON FOR AN EXTENDED TIME.
“THIS CAN CAUSE (1) AN INTERMITTENTLY INOPERATIVE BRAKE/TAIL LAMP BULB OR (2) A SHORT CIRCUIT THAT OPENS A FUSE CAUSING INOPERATIVE BRAKE LAMPS (INCLUDING THE CENTER HIGH-MOUNTED STOP LAMP) OR TAIL LAMPS. A FOLLOWING DRIVER MAY NOT KNOW WHEN THE BRAKES HAVE BEEN APPLIED, AND A REAR-END CRASH COULD OCCUR WITHOUT PRIOR WARNING.”
Bonus! A Piston Slap Nugget of Wisdom:
The lesson learned is twofold: always find recalls or TSBs that answer your problem and get them fixed before your Saturn dealer bites the dust. And if you live in Canada, you’d better get moving sooner than later.
[Send your queries to mehta@ttac.com]
I bet the distorted housing also likes to let in water to the trunk like a Neon or something.
I have a Ford ZX2 that also has the dash lights and tail lights on the same circuit. In my case, the short turned out to be a tag light housing that was allowing water to get in with the bulb. The glass bulb had cracked open, but the moisture provided enough continuity to melt the socket.
Of course, I found the short on my car by putting a big fuse in and following the smoke. I advise you do not follow my example.
I had a Jetta that had the dome lamp on the same circuit as some anti-theft component. The dome lamp shorted, blowing the fuse, and the car would no longer start since the anti-theft device had no power. To make matters worse, the fuse in question wasn’t in the normal fuse compartment, it was in a hidden panel underneath the dashboard. It took the dealer over two weeks to figure out the problem. By the time it was fixed, I had bought a Japanese car to replace the VW (this wasn’t the first ridiculous repair it had required).
Pull the light bulb sockets from the rear light assemblies and examine closely. Pull the bulbs and examine each socket, looking for corrosion, etc. Look at the wiring, if it is visible, to see if it looks like it is getting pinched as it routes back through the body. I am not sure what the resistance should be on a tail light circuit but if you can find that out and check it with an ohm meter you might be able to determine where in the circuit the short is occuring. Looking for moisture or a leak in the trunk (use a garden hose) is a good idea too.
I was thinking water in the lens. I saw a car with a fishbowl back there. When the light came on you could see the waves.
This reminds me of one of the only good things about the 71 Opel 1900 I had. It was wired so that the left marker lights and right taillight were on one fuse, the right marker lights and left taillight on the other. This meant that one fuse problem wouldn’t take out both your taillights.
When I lived in Tampa, a lot of cars had water trapped in the taillight lenses. I doubt much has changed in 11 years. Look there.
The electricals on your car were designed by Europeans. You are doomed. I’m sorry.
The Neons were great at getting water in the tail lights. When they were first launched I used to see it all the time. Kind of funny actually…my wife and I always joked about putting goldfish in them.
BTW the same thing happens to the headlight assemblies of Mitsubishi Outlander front headlamp assemblies.
Funny, my first company car was a 90 Cutlass Ciera. Good car actually, but it had one vexing problem…when I pressed the button to release the trunk lid, a fuse blew. The interesting part was it was a fuse that had NOTHING to do with the trunk lid. It was quite a mystery.
I had the same problem as this Saturn in my 1988 Dodge Ramcharger. Road debris/salt had built up on the 4-pin trailer wiring harness and moisture shorted out the electricals, causing the fuse for the tail/dash lights to blow. Contact cleaner and a plug housing under the bumper fixed it. Only other time I had it happen was on an empty trailer I pulled that about exceeded the truck’s tow rating just by itself. I think the long trailer light wires had enough resistance to blow the fuse out also. Towing at night required dialing the IP lights off so that brake lights could work.