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My son has a 04 Gt electical problem. The car drives fine then when he stops the battery dies. We replaced the battery, then the Altenator. Ran fine for a few days then battery died and not even the lights come on! Any ideas on whats happening?
 

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How long have you had the car?
He doesn't have any aftermarket alarms or amplifiers that might be causing a parasitic battery drainage, does he?
 

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+1 if he has an aftermarket sound system because it could be a bad ground connection to radio and/or amplifier. Make sure the ground cable from battery has good contact too. Also, check that the alternator power wire and remote wire are not touching any metal parts.
 

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Agreed with everything above. You have a parasitic drain on the battery......

Here are a few way to check it and try to track it down.

take off one of the battery terminal ends, (preferably the negative) and run the test light or amp meter in series from the battery post to the cable end, see if it lights up.

If it does, then you will want to start pulling fuses one by one until it goes out. I would start with the fuses inside the car. When it goes out, then that is the circuit that is causing the draw. If not, then the battery is bad, as it can't hold a charge.

The recommendation for maximum parasitic drain is around 30 mA (0.030 amp). A typical drain today actually falls into the 7-12 mA range, even though some vehicles do approach the maximum. Multiply the drain (in amps) by the time (in hours) the battery sits without being recharged. The result is the amount of AH consumed by the parasitic drain. The actual drain may be small, but over time the battery grows steadily weaker.

ALSO........BIG NOTE: Just remember to keep all of the doors closed when you do this and disconnect the hood light if there is one.
 

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The acceptable parasitic drain for our cars is 50mA. There are a few things you have to do to test this, first you will need an amp meter (multi meter will work also, anything that reads amps) and a jumper wire. The jumper wire will save some headache since you have to wait around 40min after the car is off and the key removed for all the electronic devices to shut down. I have attached the instructions (cut and paste) from the Ford Manual on how to test the battery drain:
Battery—Drain Tests

Note:
No production vehicle should have more than a 50 mA (0.050 amp) continuous draw.

Check for current drains on the battery in excess of 50 milliamps (0.050 amp) with all the electrical accessories off and the vehicle at rest. Current drains can be tested with the following procedure:

WARNING:
Do not attempt this test on a lead-acid battery that has recently been recharged. Explosive gases can cause personal injury.

CAUTION:
To prevent damage to the meter, do not crank the engine or operate accessories that draw more than 10A.

Note:
Many modules draw 10 mA (0.010 amp) or more continuously.

Note:
Use an in-line ammeter between the battery positive or negative post and its respective cable.

Note:
Typically, a drain of approximately one amp can be attributed to an engine compartment lamp, glove compartment lamp, or luggage compartment lamp staying on continually. Other component failures or wiring shorts may be located by selectively pulling fuses to pinpoint the location of the current drain. When the current drain is found, the meter reading will fall to an acceptable level. If the drain is still not located after checking all the fuses, it may be due to the generator.

Note:
To accurately test the drain on a battery, an in-line digital ammeter must be used. Use of a test lamp or voltmeter is not an accurate method due to the number of electronic modules.

1. Make sure the junction box/fuse panels are accessible without turning on interior and under hood lights.

2. Drive the vehicle at least five minutes and over 48 km/h (30 mph) to turn on and exercise vehicle systems.

3. Allow the vehicle to sit with the key off for at least 40 minutes to allow modules to time out/power down.

4. Connect a fused jumper wire between the negative battery cable and the negative battery post to prevent modules from resetting and to catch capacitive drains.

5. Disconnect the negative battery cable from the post without breaking the connection of the jumper wire.

6. Note:
It is very important that continuity is not broken between the battery and the negative battery cable when connecting the meter. If this happens, the entire procedure must be repeated.

Connect the tester between the negative battery cable and the post. The meter must be capable of reading milliamps and should have a 10 amp capability.

7. Note:
If the meter settings need to be switched or the test leads need to be moved to another jack, the jumper wire must be reinstalled to avoid breaking continuity.

Remove the jumper wire.

Note:
Amperage draw will vary from vehicle to vehicle depending on the equipment package. Compare to a comparable vehicle for reference.

Note:
No production vehicle should have more than a 50 mA (0.050 amp) draw.

8. If the draw is found to be excessive, pull fuses from the battery/central junction box one at a time and note the current drop. Do not reinstall the fuses until you are finished testing.

9. Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is still excessive.


Battery—Electronic Drains Which Shut Off When the Battery Cable is Disconnected

1. Repeat the steps of the battery drain testing.

2. Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry lamps to turn off if equipped.

3. Connect the ammeter and read the amperage draw.

The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds 50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the battery/central junction box one at a time to locate the problem circuit.
 
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