2008 V8 Explorer -- Battery Light stays on for the first mile of driving

[buschman]

I did a search but didn't find anything quite like what I'm seeing. The battery/voltage light comes on when the vehicle is started and stays on for a mile or so, then it goes off. This is an '08 V8.

I've checked the battery voltage, it's ~12.7V with the engine not running. When the engine is started it initially drops to 11.65V then after a couple of minutes it will rebound to ~13.5V.

I'm guessing the alternator is starting to go but was curious if anybody's seen this behavior before. Once the voltage warning icon shuts off the vehicle seems to work fine -- the "Check Voltage" warning is replaced by "Charging System OK". Any recommendations?

 

[east1la]

I did a search but didn't find anything quite like what I'm seeing. The battery/voltage light comes on when the vehicle is started and stays on for a mile or so, then it goes off. This is an '08 V8.

I've checked the battery voltage, it's ~12.7V with the engine not running. When the engine is started it initially drops to 11.65V then after a couple of minutes it will rebound to ~13.5V.

I'm guessing the alternator is starting to go but was curious if anybody's seen this behavior before. Once the voltage warning icon shuts off the vehicle seems to work fine -- the "Check Voltage" warning is replaced by "Charging System OK". Any recommendations?

take it to a auto parts store, so they can do a battery, and alternator test . I believe they can do test for free.

 

[Bill MacLeod]

Battery could be on its last legs. Should immediately jump to 14+ volts when started. So either battery or altenator? Have both tested.

Check both battery terminals for corrosion build up.

 

[buschman]

Updated: 2008 V8 Explorer -- Battery Light stays on for the first mile of driving

This problem has continued to be intermittent, the charge light continues to come on once a day or so and quickly goes back off.

I removed the alternator, had it tested (it passed), and cleaned all the connections between the alternator, the power distribution box, and the battery but it still acts up.

On a whim I bought a 12V plug-in voltmeter (http://www.amazon.com/Equus-3721-Battery-Charging-Monitor/dp/B000EVWDU0/ref=sr_1_1?ie=UTF8&qid=1329320851&sr=8-1, this is probably the best $15 I've ever spent.

The resting battery voltage is fine, I can watch the system voltage increase from ~12.65V to ~14.2V once the engine is started. When the charge light comes on the voltage immediately drops to ~11.9V; shortly thereafter it rebounds.

It looks like I'm for a new alternator after all.

 

[EX-SV]

My 2007 Explorer battery crapped out last December at 52K miles.

 

[east1la]

This problem has continued to be intermittent, the charge light continues to come on once a day or so and quickly goes back off.

I removed the alternator, had it tested (it passed), and cleaned all the connections between the alternator, the power distribution box, and the battery but it still acts up.

On a whim I bought a 12V plug-in voltmeter (http://www.amazon.com/Equus-3721-Battery-Charging-Monitor/dp/B000EVWDU0/ref=sr_1_1?ie=UTF8&qid=1329320851&sr=8-1, this is probably the best $15 I've ever spent.

The resting battery voltage is fine, I can watch the system voltage increase from ~12.65V to ~14.2V once the engine is started. When the charge light comes on the voltage immediately drops to ~11.9V; shortly thereafter it rebounds.

It looks like I'm for a new alternator after all.

good to hear you found the problem.

 

[Cody Kimbrough]

Mine is doing the same thing and I have replaced the battery and the alternator. Started right up and ran for a half hour. Shut it off and came back to start it back up about five minutes later and won't start. If it does, it runs like it is missing on 7 cylinders. Anyone able to help?

 

[buschman]

Mine is doing the same thing and I have replaced the battery and the alternator. Started right up and ran for a half hour. Shut it off and came back to start it back up about five minutes later and won't start. If it does, it runs like it is missing on 7 cylinders. Anyone able to help?

Check your battery voltage with the vehicle off, then check it again once the vehicle has started. You should see the voltage increase when the engine is running - that will tell you if the alternator is charging.

If your engine is running that rough then your check engine light should be on. If that's the case you'll need to pull the trouble codes to get to the bottom of it.