How to diagnose a problem that only happens first thing in the morning?

Dear Car Talk | Apr 01, 2008
Dear Tom and Ray:
We have a 2002 L300 V-6 Saturn. The turn signals will not work in cold weather (below 30 F) until the car has been driven and therefore warmed. The hazard lights will work, however. The dealer says that he doesn't know what causes the problem, and of course by the time we drive it to the dealer, the car is warm and the problem is gone. Any suggestions? -- Richard and June
TOM: Have you considered relocating to Key West? If it ever gets close to 30 F down there, you can drive out to the orange groves and park next to the smudge pots.
RAY: Actually, if you have a problem that occurs only first thing in the morning, or when the car is ice-cold, you should make arrangements to drop the car off at your mechanic's place the night before your appointment.
TOM: Just make sure he has a secure place to leave it outside. If he leaves it inside, it'll be nice and toasty in the morning, and he still won't be able to experience the problem.
RAY: And if he leaves it out on the street and he's in a neighborhood like where my brother lives, your car could get vandalized or stolen.
TOM: Of course, if the car gets stolen, you won't have the turn-signal problem anymore. But I don't think that's the solution you're looking for.
RAY: If you came to me with this problem, the first thing I'd do is replace the hazard-lights switch. That's in the dashboard, right behind the hazard switch itself. That switch has the flasher built into it for both the hazard lights and the directional lights.
TOM: If that doesn't fix it, your mechanic can try plugging in a new multifunction switch. That's the stalk sticking out of your steering column that controls your turn signals, your wipers, your bright lights and your in-dash lava lamp. The contacts in that switch just might have worn out over time.
RAY: But I'd bet on the hazard switch. If the mechanic has the car when it's cold, when the directionals are actually misbehaving, he can test all this stuff in five minutes, out in the parking lot. Good luck, guys.
We have a 2002 L300 V-6 Saturn. The turn signals will not work in cold weather (below 30 F) until the car has been driven and therefore warmed. The hazard lights will work, however. The dealer says that he doesn't know what causes the problem, and of course by the time we drive it to the dealer, the car is warm and the problem is gone. Any suggestions? -- Richard and June
TOM: Have you considered relocating to Key West? If it ever gets close to 30 F down there, you can drive out to the orange groves and park next to the smudge pots.
RAY: Actually, if you have a problem that occurs only first thing in the morning, or when the car is ice-cold, you should make arrangements to drop the car off at your mechanic's place the night before your appointment.
TOM: Just make sure he has a secure place to leave it outside. If he leaves it inside, it'll be nice and toasty in the morning, and he still won't be able to experience the problem.
RAY: And if he leaves it out on the street and he's in a neighborhood like where my brother lives, your car could get vandalized or stolen.
TOM: Of course, if the car gets stolen, you won't have the turn-signal problem anymore. But I don't think that's the solution you're looking for.
RAY: If you came to me with this problem, the first thing I'd do is replace the hazard-lights switch. That's in the dashboard, right behind the hazard switch itself. That switch has the flasher built into it for both the hazard lights and the directional lights.
TOM: If that doesn't fix it, your mechanic can try plugging in a new multifunction switch. That's the stalk sticking out of your steering column that controls your turn signals, your wipers, your bright lights and your in-dash lava lamp. The contacts in that switch just might have worn out over time.
RAY: But I'd bet on the hazard switch. If the mechanic has the car when it's cold, when the directionals are actually misbehaving, he can test all this stuff in five minutes, out in the parking lot. Good luck, guys.
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