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Electrical System

Conventional or Platinum Spark Plugs

Q: What are platinum spark plugs?

A: Platinum plugs last much longer than regular conventional spark plugs. Platinum spark plugs can be single or double platinum. Single platinum plugs one have platinum on the center electrode. Double (or dual) platinum plugs have a platinum center electrode and a platinum pad on the negative electrode. The spark occurs between these two electrodes. Platinum resists corrosion and extreme heat, maintaining the required gap for long periods of time. Platinum spark plugs are generally guaranteed for 100,000 miles.

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Fusible Link

Q: What is a fusible link?

A: A fusible link is a type of circuit protector. It is a short piece of wire that has a smaller diameter than the rest of the circuit. If too much current runs through the circuit, the wire overheats and melts, opening the circuit. When a circuit is open, no electricity can flow. The fusible link has a nonflammable insulation that bubbles to indicate to the technician that it has blown.

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Turn Signal Flasher

Q: My turn signals don't flash on either side. I checked all the bulbs and they are OK. What should I check out next?

A: If your bulbs are OK but don't flash then the turn signal flasher may be faulty. Check your owner's manual for the location.

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Horn Stopped Working

Q: My horn stopped working. Is it really necessary to have this fixed? Is there something I can check?

A: The horn is a safety device and should be fixed on your vehicle. Look in your owner's manual to locate the fuse for this electrical circuit. If the fuse is not the problem, the electrical connections on the horn should be checked. You should also use a test light to see if you have 12 volts of power at the horn when the horn button is pressed. If you have power, then you have a bad horn. If you don't have any power at the horn then the horn relay, bad horn switch, or a broken or corroded wire may be the culprit. Since some horn buttons are integrated with the air bags, I would leave disassembling the steering wheel for the professionals.

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Shorted Battery

Q: When I install a new alternator and start the engine, after about 45 seconds the alternator gets very hot and starts smoking. I've gone through 2 alternators so far. Can you tell me what the problem could be?

A: Sounds like the battery may be defective or shorted. The alternator is trying to put out too much current. Alternators are not designed to run at 100% amperage output for long periods of time. They are designed to keep a battery charged as energy is used. Check to make sure you don't have the polarity reversed on the battery. The red wire goes to the positive and the black wire goes to the negative. Trace the negative wire and make sure the ground connection is tight and not corroded. Be sure your battery terminal ends are also clean.

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Jump Start - Wires Crossed

Q: My car had a bad jumpstart with wires being crossed. Now the instrument panel gauges, the power windows, and air conditioning do not work. What is the problem?

A: When the wires were crossed, the polarity (flow of electrical current) was reversed. Reversing the polarity in the electrical system can cause serious damage. Check the fuses, circuit breakers, and fusible links in the electrical circuits that have the problem. After that, the components may have fried. Your best bet is to take the vehicle to a shop that specializes in auto electric repairs.

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Alternator or Battery

Q: My car will not start. I am getting a clicking sound when I turn the key. But when I try to jump-start the car it starts right up. After I jump-started it, I let it run for 20 minutes and then shut it off. When I went to try to start again, it just clicked. I jump-started it yet again, but this time I let the cables stay attached for 10 minutes. Now the car starts several times with no problem. What is happening here?

A: Sounds like an alternator. When you left the cables on for 10 minutes the other car's charging system may have recharged your battery. The best way to tell is to use a multimeter set to DC Volts to measure the voltage at the battery while your car is running. With the car running you should get a reading between 13.5 to 14.5 DC volts at the battery. If you are only receiving a reading of 12.0 to 12.6 DC volts while the car is running, then the alternator is probably bad.

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Anti-Corrosion Battery Washers

Q: I just purchased a tool to clean the battery posts on my car. The tool also came with two felt washers - one red and one green to be placed under the battery terminals. Which post does the red washer go onto and which post does the green washer go to?

A: Put the red washer under the positive side and the green washer under the negative side. The colors are for reference if someone is jump-starting the vehicle. Black and green both mean "ground" or negative. These pads are chemically treated to reduce corrosion. The colors are only for visual reference, they don't perform the function differently.

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Automatic Belt Tensioner

Q: I was told that a serpentine belt should last 50,000 miles or more. But on my car I had to replace the serpentine belt twice over the last year. What could be the problem?

A: Serpentine belts should be replaced every 4 years or 50,000 miles. You should not have to replace the serpentine belt twice in one year. The problem could be a worn automatic belt tensioner and/or idler pulley. The belt tensioner keeps the belt tight and vibrations to a minimum. If the bearing on the tensioner is worn, the belt may get out of alignment causing wear on the sides and fraying. If the spring on the tensioner is worn, the belt can slip and cause glazing of the belt's surface. Glazing leads to belt squealing. When replacing the belt, check the belt routing diagram sticker (usually in the engine compartment) to make sure you correctly installed the belt.

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Battery Core

Q: When I purchased a new car battery the store added on a $5.00 fee called a core charge. What is a core charge?

A: It is illegal to dispose of a lead acid car battery in your household waste. Car batteries have several pounds of toxic lead and approximately a gallon of sulfuric acid. The $5.00 fee is imposed to encourage you to return the old battery to the retailer so it can be properly disposed and recycled. In most places, retailers that sell car batteries are required to accept old ones. Most new lead acid car batteries incorporate more than 60% of recycled materials.

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Battery Corrosion

Q: My battery cables are corroded. How do I clean them and what can I do to make sure the corrosion doesn't come back?

A: Be sure to wear safety goggles, a dust mask, and rubber gloves. You do not want to get the corrosive dust or sulfuric acid in your eyes, in your lungs, or on your skin. First, clean cables with a mixture of baking soda and water. You only need about one tablespoon of baking soda per pint of water. A small wire brush works well to scrub the cable ends. After cleaning, rinse the terminals off well with water. If you need to remove the cables to get at all the corrosion, remove the negative cable first and then the positive. When reattaching the cables, install the positive cable first and then the negative. Use an anti-corrosive spray over the cable ends to minimize the likelihood of the corrosion coming back.

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Battery Life

Q: What is the average life and cost of a car battery?

A: Car batteries commonly last around 5 years. The battery's life is dependant on the environment, the car's charging system, and usage. If your battery is more than 4 years old, get it load tested at an auto repair facility. The load test will indicate if your battery is close to failing. A new battery commonly costs between $50-100 and is cheap insurance to keep your car starting even on those cold days.

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Battery Life in Extreme Heat and Cold

Q: How does extreme heat or extreme cold effect a car battery?

A: During severely cold temperatures, the battery's cranking power lessens. This is caused by an increase in internal resistance and a lessening of the efficiency of the chemical reactions. A discharged battery can also freeze, causing the casing to crack. During extremely hot temperatures, the battery's electrolyte can evaporate. When the electrolyte is low, the cranking power is reduced. Extreme heat and extreme cold can decrease the overall life of the battery.

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Battery Light On

Q: I replaced the battery when my car's battery light came on but it did not fix the problem. What else could be causing the light to come on?

A: The alternator may not be recharging the battery. To complete a simple test on the alternator, follow these steps. Obtain a voltmeter that can test direct current (DC) voltage. Connect the voltmeter to the battery. With the engine off, the reading should be around 12.6 volts. Start the engine. The voltmeter now should show a reading of 14.0 to 14.5 volts. If the reading is less than that, the alternator may not be recharging the battery as required.

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Battery Prorated Warranties

Q: I have a three-year-old battery that needs replacing. What does it mean when the battery has a "prorated" warranty?

A: Even if your car battery has a 5-year warranty, this doesn't mean you will get one for free for the whole 5-year period. Depending on the battery manufacturer, a free replacement period usually lasts between 6-18 months. If your battery is three years old, you will pay a per month charge from the original purchased date to get a replacement. Unfortunately, the prorated cost in the 3-4 year period is sometimes higher than the original battery cost. If this is the case, look for a new battery that has a longer free replacement period.

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Battery Trouble

Q: I purchased a used car and have not had the battery checked. What happens if the battery dies while I am driving?

A: A battery commonly won't give you trouble as the engine is running. The alternator provides the current at that time. You will notice battery troubles when you shut the car off and go to re-start. If the engine cranks slow, the battery may be getting weak. A weak battery, one that does not hold or accept a good charge from the alternator, can cause premature failure of the alternator. Most car batteries last about 5 to 6 years. Parts stores and service centers can "load" test your car's battery.

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Belt Squeal

Q: When I accelerate I hear a high-pitched squeal coming from the engine. What could be the problem?

A: Your vehicle may have a loose or glazed drive belt. Drive belts turn the water pump, air conditioning compressor, power steering pump, and alternator. When you accelerate you are putting more stress on the engine. As the belt is forced to rotate faster it may be slipping. The slipping can cause a squealing noise. Some belts can be tightened manually, while others have a tensioner that keeps them tight. Look for cracks, pieces missing, or fraying. A new belt will cost between $5.00 and $50.00.

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Blower Motor Stays On

Q: The heater fan stays on high speed, even when the key is turned to the off position. I have to disconnect the battery to get it to shut off. What is the problem?

A: Your vehicle most likely has a relay type blower motor control system. The blower motor relay is possibly stuck. When the fan speed is set to the HI position, an electrical current energizes a coil inside the relay. The energized coil causes a set of contact points to close, pulling the current through a fusible link from an electrical junction block. The contact points inside the relay may be stuck, keeping the current flowing to blower motor. You will most likely need to change the blower motor relay to solve the problem.

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Frozen Wipers

Q: During cold winter mornings my husband turns on the wipers to push the snow off the windshield. Is this bad for the wipers?

A: Turning the wipers on before clearing snow could burn out the wiper motor, strip the wiper arms, or blow the wiper fuse. Anytime it is below freezing outside make sure the wipers are not frozen down before turning them on. Lift them up carefully so you don't rip the rubber blade or bend the wiper arm. If the wiper is really frozen down hard and you are unable to break it free, you should turn on the defrost to melt the ice on the windshield. It is also a good practice to always allow the wipers to go to the "park position" before shutting off the ignition.

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Fuse Location

Q: My heater fan stopped working. Where would I find the fuse panel?

A: Fuse panels can be located in various places: under the hood, under the dash, driver's side edge of the instrument panel, or in the glove box. Look in your owner's manual's index under "fuses and circuit breakers" to find the specific location on your vehicle. Your owner's manual should also show you a diagram of the panel with all the fuses identified. Look under "climate control system", "heater", "htr a/c", or "blower motor". You can use a plastic fuse puller (usually provided and placed inside the fuse block cover) to remove the fuse. Look through the plastic part of the fuse to identify if it is blown. There is a wire filament in the fuse. If it is broken, you have found your problem. If the fuse is not blown, you may need a new blower motor.

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Fuse Ratings

Q: I have a fuse that continues to blow in my car. Can I replace it with one that has a higher amp rating to keep it from blowing?

A: Never replace a blown fuse with one that has a higher amperage rating. Severe electrical damage could result. The fuse needs to be the weak link in order to protect components in the electrical circuit. If the fuse continues to blow, too much current is trying to get to the intended load. Bring your car to a shop that specializes in auto electric problems.

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Headlight Bulb Keeps Burning Out

Q: What would cause my headlight bulb to blow out frequently?

A: Make sure the headlight lens does not have any cracks. If moisture is getting in it will burn out quicker. Also check to make sure the electrical socket is not corroded. If it is, use an electrical cleaner and then put a dab of dielectric grease in the socket. When installing the new bulb, do not touch the glass part. Oil from your hands may shorten the bulb's life.

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Headlight Bulb Replacement General Procedure

Q: How do you replace a headlight bulb?

A: Your owner's manual should describe the specific procedure for your vehicle. The following is a general procedure. Open the hood and look behind the headlight assembly. You should only have to turn a retainer clip that holds the bulb in place. After the retainer clip is removed, carefully pull on the bulb. It may seem a little snug...it has a rubber O-ring gasket that keeps it tight. Once the bulb is removed, lift up on the clips that hold the wiring harness to the bulb. Remove and replace the bulb. Do not touch the glass part of the new bulb...it will shorten the life. Reverse procedure to reinstall.

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Headlight Burnt Out

Q: How difficult is it to replace a blown out headlight?

A: Most vehicles today have composite headlight bulbs. On cars that have composite headlights you do not replace the outer glass of the headlamp, just the bulb inside the casing. These bulbs are relatively easy to replace. Owner's manuals will commonly explain how to replace headlights. To replace a composite headlight bulb you will need to pop open the hood, locate the bulb behind the headlight casing, turn the fastener that holds the bulb in place, unplug the old bulb, and install the new bulb. When installing the new bulb, do not touch the glass part. Oil from your hands may shorten the bulb's life.

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Serpentine Belts

Q: My mechanic told me that I need a new serpentine belt. What is a serpentine belt?

A: A serpentine belt is sometimes referred to as a fan belt. However, a serpentine belt may or may not rotate the fan. It is flat on one side and has grooves that run parallel with the belt on the other. The serpentine belt connects the engine's crankshaft, alternator, water pump, power steering pump, air conditioning compressor, and sometimes the fan. If the serpentine belt breaks, you will need a tow. To be on the safe side, replace it about every 50,000 miles.

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Starter Grinding

Q: When I turn the key to start my car I hear a grinding noise. The car starts and runs fine. I only hear it when I am starting the car. What could be the problem?

A: Three things can commonly cause this sound. The starter drive in the starter may be faulty. The starter drive's purpose is to engage the flywheel to crank over the engine. If this drive isn't fully engaging a grinding sound is heard. Another possible problem could be the flywheel. The flywheel is connected to the engine's crankshaft. The starter drive engages to the ring gear (teeth circling the flywheel). If the ring gear is damaged a grinding sound is heard. Finally, a loose starter could also cause this type of grinding. Check the mounting bolts to make sure they are tight.

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Taillight Fuse

Q: What could be causing my truck's taillight fuse to continue to blow? Can I just put a higher amp fuse in the fuse box?

A: A fuse blows due to an overload of electricity through a circuit. A short circuit or a component drawing too much current can cause this. A shorted circuit may be more likely in your case. Many trucks have wiring for trailers that can become problematic. When trailer wiring is installed, aftermarket "T" plugs can be used that plug directly into the wiring of the vehicle. Instead of using "T" plugs, sometimes trailer wire connectors are just spiced into the truck's wiring. Check all connections for corrosion or wires that have the insulation removed. Also check the taillight bulb sockets for corrosion. Use dielectric grease in the sockets and in trailer wiring connections to reduce corrosion. If the fuse blows only when you plug in the trailer, the trailer wiring is the culprit. Never replace the fuse with a higher rated fuse. Serious electric damage could result.

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Wiper Motor Faulty

Q: I have a 1998 Honda Civic and my windshield wipers won't stop. It was raining really hard so I put it on the 3rd setting (the fastest speed). When it stopped raining, I turned it off but it didn't stop. It kept going at the medium speed. What could be the problem?

A: There is a technical service bulletin on your vehicle for that issue. A faulty wiper motor can cause the wipers not to turn off or park in the correct position. Replacement of the wiper motor is necessary. The motor costs around $100 and will take about an hour to replace.

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