Click and Clack Talk Cars

By Tom and Ray Magliozzi
Monday November 05, 2001

Looks like it’s time for a new belt 


Dear Tom and Ray: 


Today I was driving to work in a nasty rainstorm. As I was driving over the large puddles of water collecting on the roadway, something strange happened. The red "battery" light on my dashboard lit up, and I had a hard time steering my car around the curve ahead. Once I got over the puddle, the problem stopped -- at least until I hit the next puddle, when it happened again. I drive a 1990 Chevy Celebrity station wagon. Is this something I should worry about? – Vic 


TOM: Steering? Nah. That's not important, Vic. Steering has always been vastly overrated. 

RAY: Don't listen to him, Vic. Here's what's happening: You have a single belt that drives all of the accessories in your car. It's a called a serpentine belt, because it's, well, serpentine. It slinks all over the engine, around various pulleys, like a snake, and it replaces all of the individual belts that used to run the accessories. 

TOM: And when you drove through those puddles, that serpentine belt got wet and started to slip. And when it slipped, all of the accessories lost power, including the alternator (which is why the battery light came on) and the power-steering pump (which is why you had a hard time steering). 

RAY: After a few seconds on terra firma, the belt dried out enough to catch, and everything was fine again. 

TOM: My guess is that it might be time to replace your belt. It might be stretched or glazed, and all it took was a little water to push it over the edge and make it slip. 

RAY: If the belt was recently replaced, or if your mechanic inspects it and says it looks fine, then you might need a new belt tensioner -- which is supposed to automatically keep the belt at just the right tension so stuff like this doesn't happen. Good luck, Vic. And get it taken care of.  



No brake lights; leaping before you look 



Dear Tom and Ray: 


I read your response to some guy named Victor who wanted to know if it was OK to use the hand brake to stop his car. Though your response was technically and mechanically correct, it needed one more paragraph. You failed to mention that even though using the hand brake will stop his car, it will not activate the brake lights. So yes, while he is blissfully going around operating his car like a moron, everyone else on the road is endangered by him. His car might be coming to a stop, but the poor sot stuck behind him (and subsequently liable for rear-ending him in most states) won't know it and might well break this yahoo's neck. Please keep the rest of us drivers in mind when answering bozos like this. Thanks. – Mike 


RAY: You're right, Mike. What is it that Ann Landers says? 

TOM: I think it's "40 lashes with a wet hand-brake cable." 



A customer who knew too much 


Dear Tom and Ray: 


We have a '95 GMC Yukon. It has a slow electrical discharge that eventually causes the battery to go dead. Then my wife finds herself stranded. The battery has been replaced, so that's not the problem. The fuse box has been sequentially checked in order to isolate the leak. No leak has shown up. We have kids in college and can't handle a new car at this time. Can you suggest another approach to identifying the cause of this electrical leak? – Rich 


TOM: This is all your fault, Rich. I think you're living a lie. You don't have a current drain at all. 

RAY: I agree. I think this is a classic case of the customer who thinks he knows too much. We have some customers who come in and tell us what's wrong with their cars. They don't tell us what the car is doing; they skip that step and just tell us what to replace. And a lot of times they're wrong. 

TOM: You went to your mechanic, I presume, and asked him to figure out what's draining current from your battery. Only, you led him down the garden path, because we don't think anything is draining current from your battery. 

RAY: If you had simply told him your battery was dying intermittently, a good mechanic would have considered three possibilities: a bad battery, a current drain or a faulty charging system. You've eliminated the battery by replacing it. You've eliminated the current drain (assuming it was checked correctly) because you checked and found no drain. And that leaves what I consider to be the most likely source of the problem: a faulty charging system. 

TOM: Normally, the battery starts the car, and then the charging system takes over. The alternator (which is the key piece of the charging system) then provides all the electricity the car needs. It provides electricity to generate a spark for combustion, electricity to run all of your accessories (like your power windows, air conditioner and lights) and electricity to recharge the battery for your next start. 

RAY: But if the charging system isn't working correctly, everything will take its electricity from the battery. The battery never gets fully recharged, and eventually it dies and leaves your wife stranded. 

TOM: So here's what you do: Go back to your mechanic and apologize for lying to him and leading him astray. Tell him you'll always give him the symptoms in the future, and never try to solve the problem for him. Based on your description of an intermittent dead battery, he should test your charging system. And my guess is he'll find the problem there. Good luck, Rich.