This DTC search page contains standard diagnostic trouble codes (DTC’s) that are used by vehicle manufacturers to identify vehicle problems. The codes provide below are generic codes that may not […]

Variable valve timing gives engine designers the best of both worlds—power with economy. It is common knowledge that it’s easier to fix a broken vehicle if you have a clear understanding of how it works when it’s not broken.

Consumers today want to stay connected and they want the drive to be an experience, especially since the amount of time Americans spend in the car has nearly doubled in the past 10 years.

Quickly open tech articles and tip clip videos from the Diagnostic News website on your smart phone and take them anywhere; the bay, on the road, you name it.

By Scott ‘Gonzo’ Weaver. At my shop I tend to do more electrical repairs than anything else. It’s what I’m known for, and sometimes I get my share of odd ball electrical problems. Sometimes it’s a factory defect where a harness has rubbed into a bracket behind the dash and shorted things out. But, a lot of the time it’s some add-on that causes the problems. Usually some sort of flashy-testosterone filled bling that the owner is using to show off his macho self to all who pass by.

By Scot ‘Gonzo’ Weaver. Jo was a new customer referred by an old-time regular. Her little KIA had a transmission problem that seemed to be getting the best of the transmission shop. The story goes that the SUV was constantly in limp mode, and would never shift properly… ever. As it always seems to be the case when a simple problem can’t be solved simply, somebody started the diagnostics off in the wrong direction. Little did I know this was a simple problem. But, as I see it, any type of diagnostic work that you do requires a certain step-by-step procedure that you must follow. Missing a step, or completely overlooking a step, usually means you’re going to miss that simple problem all together. This was no exception.

Our Time Relationship Table is most useful for technicians getting started with a labscope. Establishing an appropriate time/division can be confusing. To reduce uncertainty it is useful to know the normal time duration of the pulses that are being evaluated. Then, select a time per division setting that will accommodate the number of pulses desired on the display screen. To accomplish a proper scope control setting the relationship of milliseconds to microseconds as well as their fraction of a second is very useful.

The U140/240 – U150/250 transmissions have their fare share of valve body malfunction making the purchase of a new or a good used one a frequent occurrence. Such was one experience with a U140E valve body in a RAV 4. The tech working on the vehicle purchased a good experienced valve body from a hard part supplier which after it was installed had no reverse unless he played with the shifter.

A tech came to me with a P0305 code on a Dodge 1500 pickup with a hemi engine. The Question was, is there a quick way to determine which direction to take in the diagnostic procedure?

By Jim Wilson. Join Jim as he illustrates how to check Mode $06 data.

By Gary Goms. Although air and fuel filter maintenance is usually considered a “no-brainer” by most import repair shops, advancing technology is changing the way we should be performing air and fuel filter maintenance.

By Jim Taylor. Under the Toxic Substances Control Act (TSCA), EPA issued a “significant new use rule” (SNUR) at the end of October for the chemical substance identified as 1-Propene, 2,3,3,3-tetrafluoro-. The chemical is also known as HFO-1234yf.

By Scott ‘Gonzo’ Weaver. Ok, you got me … I’m a Flasher … or more to the point a Re-flasher. With today’s cars and components, it’s not uncommon to have to flash some driveability controller or theft system. As an independent shop, most of the re-flashing you can do will be for driveability situations or theft systems. Right now, the federal laws (Clean Air Act) only requires the manufacturer to give access to the “emission” related systems which means, an aftermarket scanner may only be able to provide you with part of a download versus the entire download.

By Gary Goms. During the summer, the speedometer on the Taurus would quit on an intermittent basis. Of course, when the speedometer would quit, the automatic transmission would default into an intermediate gear and fail to shift into the higher ranges. Although a local transmission shop installed a new VSS and performed other repairs as well, the Taurus ran only a few days before the problem resurfaced.

By Gary Goms. Although digital storage oscilloscopes or “lab scopes” have now become standard equipment for most modern automotive repair shops, they still possess a mystique that tends to intimidate many technicians. Right off the top, a lab scope is basically a voltmeter that displays voltage signals along a time base. The vertical scale measures the amplitude or amount of the voltage and the horizontal scale measures an incremental time line along which the signals are displayed.

By Gary Goms. MIL diagnostics continues to be a “hot” topic for many import shops simply ­because the definition of the word continues to change. Looking at the history of modern vehicle diagnostics, most veteran technicians can remember the days when vehicles had no on-board diagnostic systems and, subsequently, ­required time-consuming pin-out procedures to diagnose electronic systems failures.

By Scott “Gonzo” Weaver. When I was a kid, I saw a movie called the “Juggernaut” with Richard Harris as the main character. It was about a cruise liner that was about to blow up because a terrorist had planted 55 gallon drum bombs all over the ship. The premise of the story line is that Richard Harris was going to save all the people on the ship by defusing the bombs. All through the movie, there were references to the different relays and electrical circuits.

By Gary Goms. Right now, the service opportunities lie mainly in the future as hybrids move out of warranty and into the independent service bays. However, it’s entirely realistic to expect hybrids to become a growing part of the automotive service market.

In the article “Gasoline Direct Injection” in the Winter Issue of the Blend’r, we uncovered the disadvantages of the gasoline direct injection (GDI) engine…

By Gary Goms. Although modern OBD II technology has simplified catalytic converter diagnostics, it’s still important to understand the basics of catalytic converter operation when dealing with a P0420 or P0430 diagnostic trouble code (DTC). DTCs P0420/P0430 indicate that ­catalyst efficiency is below predetermined thresholds on cylinder banks 1 and 2, respectively. In the following text, I’ll explore the basics of catalytic converter chemistry and summarize how common catalytic converter failures can be diagnosed.

Part 3: Precision Low Current Measurements for Driveability Diagnosis. Automotive technicians often use a DMM connected to a clamp-on current probe to measure current flow (amperage) in a circuit. Typical items tested are starter motor draw, blower motor draw and alternator output. The current probe clamps around a wire in the circuit under test and using voltage from its own battery (usually 2 AAA’s or a 9 volt) sends a signal to the DMM. Most current probes output 1mV for each amp detected in the circuit.

By Omar Trinidad. Illustrating the internal operation of a voltmeter while a technician is testing a series circuit with one or two loads is a helpful way to explain how the tool works. We’ll start right off with an example.

We are going to do something a little different this time in the Fine Tuning department. We ran into a diagnostic case study you might be interested in. It involved a 2001 Chevrolet Impala with about 40,000 miles on it. The A/C fan and cruise control would intermittently stop working while the customer was driving. There seemed to be no rhyme or reason to the failure. The vehicle could be driven for days before the problem would occur.

We continue our investigation of engine knock sensors with a look at one and two-wire sensors.

In the previous issue of Counter Point, we discussed the various causes of engine knock. Prior to the age of electronic engine control, an engine designer had a limited number of effective tools to guard against engine knock. Principle among these were combustion chamber design, the octane of the fuel used and mapping of the spark advance curve. The designer couldn’t risk the possibility of engine damage caused by knock, so it was always necessary to keep the engine well short of the point where it might begin. This assured engine longevity, but hurt performance.

Part 2: Analyzing Amperage Results When Testing Ignition Coils with a Low Amp ProbeCheck out Part 2 of Barry Gersten’s Current Ramping series. This time, he covers how to analyze […]

Engine knock limits performance and can cause permanent damage. This time, we’ll look at its causes.

Under certain conditions, combustion in a spark ignition engine can degrade into an abnormal preignition process that causes a “knocking” or “pinging” sound. This undesirable combustion process limits the engine’s output and specific efficiency levels. It occurs when the fresh air/fuel mixture preignites in spontaneous combustion before being reached by the expanding flame front.

Part 1: Getting Started – How to shop for a well designed Low Amp Clamp. In order to choose the best Low Amp Clamp it is important to know the limitations of the various Low Amp Clamps. Any limitations are usually revealed in the Manufacturer’s Spec Sheet Data.

A number of emissions programs are conducting an emissions test on OBD II vehicles that has been nicknamed a “plug and play” test. Perhaps something similar to this has already happened to you. A customer brings his vehicle to your shop because the malfunction indicator lamp (MIL) is glowing on the dashboard. After retrieving the stored diagnostic trouble codes (DTCs) and freeze frame data, then conducting a thorough diagnosis, you determine the cause of the fault. The defective part is replaced, the DTCs and freeze frame data are cleared from the Powertrain Control Module (PCM) memory and the vehicle is taken for a road test. After the road test, the PCM’s memory is rechecked for stored or pending DTCs. None are found.

Oil is killing our cars!” warns Keith Ansell, President of Foreign Parts Positively. “Be aware that ‘New and Improved,’ or even the ‘standard products’ we have been using for many years, are destroying our cars. It isn’t the same stuff we were getting even a year ago.”

Although a bit of a sensationalist, Keith is not completely out of line and he isn’t the only Internet auto expert touting the effects of the industry required ZDDP (zinc dialkyl dithiophosphate) decrease in motor oil.

If you’ve spent hours struggling to master a new computer software system, you can well understand how a modern auto technician might feel when confronted with not just one, but hundreds of different software configurations built into the platforms of the 17 different vehicle manufacturers now being sold in our domestic market.

While new car recalls have been among the biggest news stories of the year, an analysis by Edmunds.com, assures consumers that despite these recent headlines, recalls were much more of a concern in decades past.

By Ken Shriner. Does ethanol usage reduce fuel economy compared to conventional gasoline? What vehicles can use ethanol-containing fuel? Can ethanol-containing fuel affect cold starting? Does it dry the fuel system? Can it cause engine deposits? Read on to find the answers to these questions and more with BG Products, Inc.

By Dave Hobbs. No matter how complex ‘smart’ charging systems appear at first glance, it still comes down to a battery, an alternator and some modules monitoring and controlling voltage regulation. We’re sure you’ve got the smarts to handle that.

Tire Pressure Monitoring Systems are and have been a required feature on U.S. Passenger vehicles since 2008. Introducing this technology to the way we maintain our vehicles has improved safety and vehicle performance, increased fuel efficiency and tire life. It also has forever changed the way autos and tires are serviced. Any operation that works on tires has been faced with serious challenges to the way they do business. Thus is the nature of change. You can either run from it (lose business) or embrace it and seize the opportunity to grow and enhance your business.

By Scott “Gonzo” Weaver. Ever wonder how your cable TV comes into your home on that single coaxial cable? In simple terms… it’s like a CAN system. A good definition of a CAN system would be: High speed communication sent via data lines to and from components.