What to do if ECM is not communicating with alternator?
Put circuit tester between bat and cable. Tested all fuses by removal. Light on circuit tester still on. Removed hot cable to alternator, tester light still on. Any help would be great. I will reserve my diagnosis until comments provide diag/options.
What should I do if my alternator keeps dying?
The alternator is essentially a generator and it keeps your battery charged while supplying additional electrical power for the other systems in the vehicle. If you have a new alternator and your battery keeps dying on you, then there’s definitely a problem that you’re going to need to look into.
Is there a bad wire to the ECM?
Suspected bad wire to ECM or ECM. The ECM in some manner controls the voltage regulator, which charges the battery. The voltage regulator works all on its own. The computer does not control it in any way. Yes the charging system goes through the pcm ,The Electronic Voltage…
Can a car battery be drained by an alternator?
While you might initially think that any problems with electrical things like lights or radio not working are directly related to the battery, the alternator is actually where most of the power in your vehicle comes from. Consider that if you were to leave the lights of your car on overnight by the next day your battery might be drained completely.
Is the alternator not communicating with the ECM?
Dodge Grand Caravan Questions – ECM not communicating with alternator’s voltage regulator. – CarGurus.ca ECM not communicating with alternator’s voltage regulator.
Can a bad ECM drain the battery all at once?
This is where the voltage regulator comes in, it allows the alternator to maintain the correct amount of voltage so that the alternator does not exceed the amount of voltage supplied to the battery. Too much voltage supplied to the battery and components can begin to fry, too little and the battery will not charge at all.
What does it mean when your alternator is not charging?
If the alternator is not charging the battery, you will have a red “ALT” or “charge” sign on your dashboard. This means that your battery is no longer being supplemented for power by the alternator. You will need to recheck the wiring because the light could also be faulty.
How can I tell if I have an alternator problem?
To differentiate an alternator problem from the battery, you will need to use a voltmeter to check for voltage. First, turn off the engine and check the battery voltage. A fully charged battery should have a reading of 12.65 volts. Next, turn on the engine and recheck the voltage. You should have a reading of 13.5 to 14.5 volts.
This is where the voltage regulator comes in, it allows the alternator to maintain the correct amount of voltage so that the alternator does not exceed the amount of voltage supplied to the battery. Too much voltage supplied to the battery and components can begin to fry, too little and the battery will not charge at all.
What should the voltage be on an alternator?
Connect the red one to the “+” battery pole and the black one to the “-“pole. You’ll immediately get a reading of the battery voltage. If everything is OK the battery voltage should be around 12.2 to 12.7 volts, depending on the condition of the battery.
How does an alternator charge a car battery?
The battery does have enough electricity alone to feed the ignition, and once the vehicle is turned on, the alternator kicks in to charge the battery. In order for this to happen, the alternator must supply the correct amount of voltage which can be anywhere from 13-14 volts.
Put circuit tester between bat and cable. Tested all fuses by removal. Light on circuit tester still on. Removed hot cable to alternator, tester light still on. Any help would be great. I will reserve my diagnosis until comments provide diag/options.
How is the maximum output of an alternator limited?
The maximum output is limited by a voltage regulator, which varies the alternator output relative to the system voltage; when the system voltage is low, the regulator increases the alternator output, and vice versa.
Can a battery voltage test be done on an alternator?
One test is not enough if you are diagnosing a charging system problem. All too often, the alternator is condemned as the source of the problem if only battery voltage is present with the engine running. If this is the case, it only means that the alternator is not charging, but does not reveal why.