ECM Archives - UnderhoodService
Engine Control Modules (VIDEO)

Accurate diagnosis of any suspected ECM-related fault is important. This video is sponsored by The Group Training Academy.

Detecting Misfire And Knock Conditions

Knock sensors are mounted on the block near the base of the cylinder head.

Nissan Code P0603 Stored For ECM Back Up Circuit

The P0603 code deals with battery issues such as low battery voltage, discharged battery or battery terminal disconnections.

Diagnostic Strategies For New Technicians

In my textbook, a piston or flame front would not be mentioned until the last chapter of the book.

ECM and PCM Calibration Numbers

Finding out if the vehicle has the latest version or calibration on a module is a required step.

The Diagnostic Shell Game: Why The ECM Can’t See A No-Code Stalling Complaint

Remember the old carnival game where a dealer hides a pea under one of a half-dozen walnut shells? After the dealer artfully shuffles the six shells, you’re supposed to pick the shell with the pea hidden under it. Good luck with that. As veteran diagnostic technicians know, diagnosing a no-code intermittent stalling complaint can be like playing the old carnival shell game. We know it’s one of maybe six sensors, but why can’t we find the diagnostic trouble code (DTC) that tells us where to find the pea?

Outsmarting The Smart Cars: ECM Replacement

The ECM’s (engine control computer) function is to control emissions, monitor and regulate engine functions as well as optimize engine performance and fuel consumption.

VIDEO: Stop-Start System Service Opportunities

Andrew Markel discusses service opportunities for vehicle stop-start systems and how several modules are involved in the activation of the feature. Sponsored by Bosch Automotive Service Solutions.

stop-start-service-opportunities-video-featured
Danger, Will Robinson! Intermittent Loss Of Power

This month’s Diagnostic Dilemma turns the page back to September 10, 2015 when I got a phone call from a local undercar shop inquiring if I had the tools to check the ECM connector pin fit on a 2012 Chevrolet Impala with the flex-fuel, 3.6L gasoline direct fuel injection engine. In response to an intermittent loss of power complaint, the shop had found a technical service bulletin (TSB) indicating that loose PCM connections can cause a loss of fuel pressure on the GDI engine’s high-pressure fuel rail and set codes P00C6 and P228C.

Three lobe cam for fuel pump
ECM Diagnostics: Troubleshooting P1518 Codes

ECM diagnostics can be a challenge because you often find yourself working after the fact. As described in the July 2015 issue of Underhood Service (“The 1,300-Mile Test Drive”), a seemingly routine loss of power and a no-cranking, no-instrument cluster, no-scan-tool communication complaint on a 2003 GMC Yukon, VIN Z 5.3-liter flex fuel engine turned out to be a major Diagnostic Dilemma.

Driveability Diagnostics and Direct Injection

Direct injection is becoming standard on more and more late-model vehicles. These systems can be a diagnostic challenge, but with the right foundation, problems can be solved profitably. Years ago, all a low-level technician needed to diagnose a fuel problem was a set of “noid lights,” a fuel pressure gauge and maybe a meter. These

Direct Injection Fuel System
Variable Displacement: The Future of the Oil Pump is Here

Almost every major OEM has an engine or engine family that uses a variable displacement oil pump that is controlled by the ECM to deliver the best possible pressure and efficiency. When it comes to improving fuel efficiency, 3% to 5% are huge numbers. Achieving those fuel efficiency numbers while also increasing the power to

Variable Displacement Oil Pumps