ECM/PCM Communication Issues (VIDEO)
Before you swap out a module that won’t communicate, do a few simple inspections. Sponsored by The Group Training Academy.
ECM and PCM Calibration Numbers
Finding out if the vehicle has the latest version or calibration on a module is a required step.
Nissan PCM Computer-Control Issues
The American writer Irene Peter said it best: “Just because everything is different doesn’t mean anything has changed.” By 2018, I thought everything had changed since the days of On-Board Diagnostics I (OBD I). Since OBD I evolved into OBD II in 1996, many things did indeed appear to be different. But, once in a great while, engineers design a vehicle that is slightly ahead of its time. For me, it was a 1995 Nissan pickup equipped with the 3.0-liter V6 engine and manual transmission. Surely being an oddity, it would start and run with the distributor disconnected.
The No-Code Conundrum: The Art Of Diagnosing What The PCM Can’t See
Doing mobile diagnostics, I obviously get more than my share of no-code driveability problems. Case in point, I was asked by a client shop to “take a quick look” at a stalling complaint on a 2003 Ford Explorer with a cable-operated throttle.
The Art of Diagnosing What the PCM Can’t See
The difficulties of diagnosing no-code drivability problems are best summed up by one of Yogi Berra’s famous quotes, “When you come to a fork in the road, take it.”
Following The ‘Electronic Trail’ As A Means To Solve PCM-Related Problems
Leave your wrenches in your toolbox because in this month’s Diagnostic Solutions, we’re going to explore how to diagnose many common powertrain control module (PCM)-related driveability and electrical problems by following what I call The Electronic Trail.
When Over-Voltages Electrocute PCMs
During the past nine months, I’ve had three instances of powertrain control module (PCM) failures on Jeep Wrangler vehicles that were evidently caused by an over-voltage condition. The first case involved an owner who requested that a local shop replace the fuel pump because his ’98 Wrangler was slow-starting in the morning.
Ford: Driveability issues due to water in the PCM
Some 1999-2003 Windstar and 2004-’07 Freestar /Monterey vehicles built prior to June 22, 2006, may exhibit engine/transmission driveability issues due to water entering the powertrain control module (PCM) or transaxle vent. The water leakage may be due to the PCM connector cover not seating completely and water leaking down from the cowl panel grille (cowl
PCM Diagnostics Case Study: No-Code Misfire Diagnosis On A 1998 Toyota 4Runner
When doing mobile diagnostic work for other shops, contributing writer Gary Goms usually sees more than his share of random no-code engine performance complaints. In the following case study, the customer of a client shop complained about an intermittent rough idle on his well-maintained 1998 Toyota 4Runner, but only when it was driven in hot weather. The client shop couldn’t duplicate the complaint, no matter how long the engine ran. Of course, the lack of DTCs didn’t help the diagnostic process.
Tech Feature: Dissecting The Control Module – PCMs, TCMs And BCMs
With the complexity of automotive electrical systems increasing steadily, manufacturers have developed troubleshooting trees and strategies to make it easier for technicians to diagnose problems. These steps and strategies are very helpful for technicians when followed, but they can also prevent them from using their cognitive skills.