Codes B2339 and C123C Pulled on Jeep Rubicon
Contributor Gary Goms pulled codes B2339 from the Cab Compartment Node and C123C from a Jeep Rubicon. Here’s how he diagnosed this dilemma.
Pulling Codes: Chevy Impala Sets Codes: P00C6 and P228C
With an intermittent loss of power complaint, Gary Goms tackles the “nuances” of GDI diagnosis and repair on a Chevy Impala.
Using a Scan Tool and Meters To Diagnose Toyota Charging Systems
If, after replacing the alternator, a customer’s Toyota returns to your shop with the battery warning light on, contributor Gary Goms advises, “connect a scan tool to determine the charging system configuration and help analyze charging output.”
Sorting Through Multiple Codes On A Chevy
Gary Goms looks at a vehicle with 11 DTCs to find the root cause of the problem. This article discusses the art of deciphering codes and physical problems that may generate multiple codes and hide the real source of a problem.
Vacuum Vitals – Looking Past the Codes & Modes
In this month’s Diagnostic Dilemma, contributor Gary Goms found himself looking into an intermittent fast idle complaint on a 2008 Chrysler Sebring. The most baffling part of the diagnosis were the DTCs indicating a major vacuum leak and the voltage drop on the APP2 graph.
Intermittent Engine Misfire Analysis
Even for an experienced diagnostic technician, attempting to diagnose an intermittent misfire condition that occurs only under specific driving conditions can be a frustrating exercise. Contributor Gary Goms breaks it down, and includes tips for using a scan tool and a lab scope.
Modern Fuel Control Diagnostics: Sorting Through the Datastream
When confronted with a fuel control problem, contributing writer Gary Goms normally uses short- and long-term fuel trims to determine if the problem is caused by one of many failures such as a vacuum leak or a leaking fuel pressure regulator. He says some aftermarket scan tools may display AFR sensor data in a confusing way, so he helps techs sort out this datastream maze.
Diagnosing Starter Misses
Contributing writer Gary Goms was called to a friend’s shop to help with a no-cranking condition on a 2006 Chevy Tahoe. After diagnosing a faulty PCM ground, locating the missing ground proved to be problematic. Find out how Gary solves The Case of the Missing Starter.
Telltale Signs Of Cooling System Component Failure
Springtime brings with it the vacation season when many families will hitch a boat or camping trailer to their fully loaded family car, SUV or pickup truck and travel to some remote wilderness hideaway. Needless to say, both the parents and their vehicle’s cooling system will be stressed out long before the trip is over.
When Should Fluids Be Replaced?
Several factors are driving modern fluid maintenance services. First, a modern vehicle’s service life often extends to well over 200,000 miles and good fluid maintenance practices are, in part, responsible for that remarkable achievement. Second, car counts in many shops are declining because late-model vehicles require less scheduled maintenance and less frequent repairs. Consequently, many shops are looking at add-on services, such as fluid maintenance, to boost shop revenues.
Take Time To Evaluate The Condition Of Brake Hydraulics
Mileage is an essential criterion for evaluating the condition of brake hydraulics. Keep in mind that, each time the brakes are applied, the master and wheel cylinder piston seals wear. Given time, the rubber cups in master cylinders wear to the point that they will not consistently seal hydraulic pressure. The result will often be a low brake pedal, poor stopping power or an intermittently sinking brake pedal.
Pinning Down Intermittent Malfunctions On OBD II Vehicles
Although post-1996 OBD II powertrain control modules (PCMs) are generally very reliable, we’re beginning to see more failures because the average age of our national vehicle fleet has now increased to about 11.5 years. Technically speaking, the PCM should store a DTC indicating some type of internal malfunction. But, in the real world, if your scan tool indicates “no communication” and asks if the ignition switch has been turned on, you obviously have a communications problem.