need help! ECM?? in 2nd Generation Dodge 24 Valve Powertrain Posted 34 minutes ago Look in the articles for the voltage drop test in the general articles under electrical. You need to see if you have any bad cables between batteries and the alternator. Make sure where the alternator bolts to the block you have clean grounds. Look for electrical loads that are drawing hard on the system. You could pull a fuse and probe both contacts with a DVM on amps DC and you can total up all the circuits. Optimally you want it as low as possible.