Electrical Archives - Page 53 of 55 - UnderhoodService
Ignition Misfires

A flashing Check Engine light and a P0301 to P0312 diagnostic trouble code is a sure-fire indication that one or more cylinders are misfiring. Occasional misfires may pass unnoticed, but a steady misfire is hard to miss. The engine usually feels rough, lacks power and uses more gas than usual. Sometimes a misfire may feel

A/C Update: Bad A/C Blowers & Fuses

One component air conditioners and heaters share in common is the blower motor. The blower motor is usually located in the Heating, Ventilation and Air Conditioning (HVAC) housing under the dash. The blower motor spins a squirrel cage fan that delivers both cold and hot air. If the driver wants cold air and turns on

Diagnostics Through CAN Networks

Since model year 2003, a growing number of domestic and import vehicles have been built with a new onboard communications protocol called CAN (Controller Area Network). CAN is essentially an engineering standard for how computers and modules talk to one another via the serial data bus in a vehicle’s wiring system. It’s a high speed

Selling Services: Anti-Seize & Studs

Last month I received a great letter from one of our readers. He was absolutely livid about the story “Double Hit” in our February issue. Ed from the Cherokee Garage in Beckwourth, CA, pointed out several incorrect items in the article. In the article, it was advised that a light coating of anti-seize could be

Slotted and Drilled Rotors: Show or Slow?

You’ve seen them on the race track. You’ve seen them on the street. You’ve seen them in speed shops, in magazine ads, online and probably on eBay, too. The product we’re talking about is slotted and/or cross-drilled high performance brake rotors. They look great, no doubt about it. Performance rotors are an excellent upgrade for

Tech Feature: Solving Intermittent Electrical Problems

Intermittent electrical faults are the bane of the auto repair business. If an electrical component has failed, or there is an open or a short in a circuit, you can usually find it fairly quickly because it isn’t hiding from you. It’s a persistent fault that can be isolated by a systematic process of elimination.

Double Hit

It’s not difficult to torque wheel fasteners properly, but it’s not difficult to foul up the job, either. We’re not using double talk here; we’re shootin’ straight from the hip. The easy part of proper wheel fastener torquing is knowing the vehicle manufacturer torque specifications for a particular passenger car, light truck or medium truck,

Alternator Diagnosis: High-Draw Accessories Merit Changes in Test Procedures

As the saying goes, “Old habits die hard.” Among the old habits that die hard is the way we test alternators. In the past, the job of the alternator or generator was simply to recharge the battery after start-up and carry minor accessory loads such as ignition, lighting, radio, heating or air conditioning clutch, and

Suspension Vibration Diagnosis

The song “Good Vibrations” by the Beach Boys may have been a big hit in its day, but there’s no such thing as good vibrations or noise when it comes to a customer’s vehicle. Vibrations are annoying and may be a warning signal that something is amiss. So don’t ignore such symptoms. Investigate any unusual

How Much Maintenance

How much maintenance is really necessary to keep a vehicle in good, running condition, safe and reliable? It’s a controversial subject for which there is no simple answer. Maintenance recommendations and requirements vary depending on the year, make and model of the vehicle, the type of driving it undergoes, the environment in which it operates,

Diagnostic Solutions: Identifying Ignition Switch Failure Symptoms

Although the basic ignition switch has remained unchanged for many years, the way it supplies electrical current to modern on-board electronics has made it a key factor when diagnosing intermittent failures in various electronic operating systems. Going back into automotive history, the ignition switch’s sole purpose on early imports was to energize the primary ignition