Alternator Ripple Testing: The Ghost In The Machine
Before computers and networks in vehicles, an alternator that was producing AC voltage or ripple through the electrical system would cause flickering lights and maybe an ignition problem. Today, excessive ripple voltage can cause communication issues with networks and communication DTCs in multiple modules.
Alternator Testing Tips
If only battery voltage is present at the battery on a running engine, does this mean the alternator is “bad?” No, it does not. It only means that the alternator is not charging, but does not reveal why. Therefore, it does not prove a faulty alternator.
VIDEO: ECM Alternator Regulation; No More Full Field Testing
Andrew Markel explains how modern alternators are designed to have their loads regulated by the ECM, eliminating the need for full field testing. Sponsored by Auto Value and Bumper to Bumper.
Remy Expands Line Of New Starters, Alternators
New starter part numbers are now available for a variety of vehicle applications, such as Chrysler, Dodge, Ram, Jeep and Ford.
Remy Adds New Part Numbers To Starter And Alternator Lines
New starter part numbers are now available for a variety of light truck and van applications, including Ford F-250, F-350, F-450 and F-550; Chevrolet Express and Silverado; and GMC Savana and Sierra.
Alternator Testing Diagnostics Are Getting More Complicated
One test is not enough if you are diagnosing a charging system problem. All too often, if only battery voltage is present with the engine running the alternator is condemned as the source of the problem. If this is the case, it means that the alternator is not charging, but does not reveal why.
Alternator Testing: What Is The Correct Voltage?
For some alternators, it’s normal to see as low as 13 volts. For some, a constant 13.6 volts is an indication of a problem. For others, it’s normal to see as high as 16 volts for long stretches. Still, it’s perfectly normal for others to see the alternator not charge at all intermittently.
VIDEO: Check The Battery When Replacing The Alternator
Andrew Markel stresses the importance of checking the battery during an alternator replacement job, and replacing it if it is worn out or will not accept a charge. Sponsored by DENSO.
VIDEO: Three Tips For Your Next Alternator Installation Job
Andrew Markel goes over the proper installation procedure for a brand new alternator. Sponsored by DENSO.
VIDEO: Alternators And AC Ripple
Andrew Markel explains how AC ripple can affect modules’ communication and even damage them. Sponsored by Bosch Automotive Service Solutions.
