Category: Car Care

See the Light (Automatic High Beam Dimmers)

It’s happened to all of us.  We’re driving down a highway at night and over a crest appears a car with its high beams blazing.  You are momentarily blinded, hoping the other driver will switch them to their low beam setting and restore your vision.

Not only do we not appreciate being blinded, face it; we don’t want to be that other driver, either.  You know, the one who forgets to turn down their high beams.

Why do we want high beams in the first place? They can improve safety when used correctly, giving drivers more reaction time since they can see farther down the road.  But research has found many drivers either don’t use them or, when they do, they frequently forget to switch to low beams.  Enter the automatic high-beam dimmer.

The quest for the perfect one began back in the 1950s, General Motors invented something it called the “Autronic Eye.” It was a phototube which sat on the dashboard and turned down your beams when it saw other headlights.  While touted as being the biggest advance in night driving safety in 30 years, it didn’t work all that well.  But as technology got more advanced, systems improved.

Today’s automatic high beam dimmers usually have a camera in the rear view mirror (pointing forward).  When the camera sees lights, software in the system’s computer attempts to determine the source of the light, whether it is an oncoming vehicle, taillights, ambient city lights, street lights or the reflection off of a street sign.  It then adjusts the headlights to operate high beams if appropriate or a less-blinding mode if they’re not.

Some automakers are striving to make their headlight systems smarter and safer by developing lamps that can avoid blinding oncoming drivers by means other than simply dimming them. One idea? Splitting the beams so they will block just the portion that shines into the eyes of oncoming drivers.

It’s a long way from the Autronic Eye. 

Autotronics of St. Peter
111 Jefferson Avenue
St. Peter, MN 56082
507.934.9290
http://autotronicsstpeter.com

Time for Differential Service at Autotronics of St. Peter?

Hello St. Peter – let’s talk differentials. If you have a rear-wheel drive vehicle, your differential is on the back axle. With front-wheel drive cars, the differential is up front. All-wheel drive and 4-wheel drive vehicles have three differentials – front, rear and in the middle. So you see, you’ve got a differential (or two or three) and it needs service now and then.

What does your vehicle differential do? Well, it compensates for the differences in speed between your outer and inner wheels in a turn. Using the dimensions of a typical car, let’s compare the distance the wheels travel from the start of a turn through to the completion of the turn.

The inside wheel travels about 12.6 feet/3.8 meters. How much farther does the outside wheel travel? About 18.8 feet/5.7 meters – over 6 feet/1.9 meters more. This means the outer tire has to rotate 9 times in the same amount of time that the inner tire has to rotate only 6 times – so the outer tire has to spin faster in order to keep up. The differential makes this possible.

The gears in the differential are cooled and lubricated by differential fluid. It’s this fluid that needs to be serviced. Small bits of the gears break off and are suspended in the differential fluid. The dirtier the fluid, the faster the gears wear.

So your Autotronics of St. Peter technician drains the old fluid out and replaces it with fresh fluid. Some differentials also need a special additive that is put in at this time.

So when should you have your vehicle differential serviced? Intervals vary from vehicle to vehicle – and may be as short as 15,000 miles/24,000 km – so check your vehicle owner’s manual or ask us at Autotronics of St. Peter. If you frequently drive with heavy loads, tow a trailer or drive in hot MN conditions, you may need to change differential fluid more often. Servicing your differential on schedule at Autotronics of St. Peter can save a pricey replacement down the road.

Give us a call.

Autotronics of St. Peter
111 Jefferson Avenue
St. Peter, MN 56082
507.934.9290
http://autotronicsstpeter.com

Not-So-Common Sense (Sensor Failures)

So your vehicle won’t start.  What’s the first thing that comes to mind?  Battery dead? Starter motor worn out? Out of gas?  Well, those are all reasons that make sense.  But your vehicle may be refusing to start because one of its computers is being warned that to do so might damage it.  Here’s how that works.

You have lots of computers in your vehicle.  They need to know the status of things so there are several sensors monitoring various things going on.  These sensors send information to the computers that adjust the fuel and air mixture so you don’t waste fuel.  They know when things aren’t quite right and prevent you from starting your engine if that’s going to damage it. 

Other sensors make sure the coolant is the right temperature, check to see you are not polluting the air and make sure other electronic components are performing their tasks correctly.

Here’s an example of a sensor doing its job.  Your engine needs oil to lubricate metal components so the friction doesn’t damage them.  Your engine has an oil pressure sensor that tells a computer called the Electronic Control Unit (ECU) if things are good to go or if there’s something wrong, maybe the oil pressure is too low to keep things lubricated.  If it is, it gives a signal for the vehicle not to start, protecting the engine. 

Of course, the sensors can go bad, too, with some of the same results.  And so someone has to figure out if it’s the sensor that’s failed or if it really has detected a problem.  That is the challenge for technicians with specialized equipment to decipher the signs.  If a bad sensor is found, it may need to be replaced.  Sometimes a thorough cleaning can do the trick.  In either case, your service facility can track down the problem and get you back on the road.  Makes sense, doesn’t it?

Autotronics of St. Peter
111 Jefferson Avenue
St. Peter, MN 56082
507.934.9290
http://autotronicsstpeter.com