Help please, ammeter drops off

[MxShawn]

Hey i need some help, my trucks in my sig, i start it up. . ammeter reads fine, voltmeter on the batt reads 13-14 volts. . its charging... as soon as i hit 60 MPH the ammeter drops off and the check gauges light comes on, test the batt. . 12 volts, not charging . . i cant shut it off and start it back up and it will charge again. . till i hit 60... i read up last night and people whos alternater went out, from what i read, the ammeter was very sporatic. . i changed the alternater and it does the same thing. . im lost. . the serpintine belt is fine. . everything else is fine. . please help. . thanks in advance

__________________

 

[gjones813]

are you sure both batteries are OK? I would have them both checked for sure to make sure one isn't interfering with the other.



also there is a electronic device sensor and I cant remember what it is called something to the affect of; tpms or timp, I really can't remember, but I have read where this sensor could cause electrical problems.



sorry I couldn't be of more help.

 

[HBarlow]

Your truck is five years old. I would take it to a good shop or retailer who can and will load test your batteries. My guess it you are due for a new pair of batteries.

 

[ryecreek]

are you sure both batteries are OK? I would have them both checked for sure to make sure one isn't interfering with the other.



also there is a electronic device sensor and I cant remember what it is called something to the affect of; tpms or timp, I really can't remember, but I have read where this sensor could cause electrical problems.



sorry I couldn't be of more help.

i beleive he's talking bout batt temp sensor there is one under each batt(they control the charge rate according to temp) ******keep yer test light away the bts are 5v*******

i'd check codes first even the key cycle code ckeck will show batt temp sensor. and for sure have both batts load tested.

 

[jelag]

Lets assume you have at least 1 bad battery that overheats... I can only assume that ryecreek answer tells us that if a battery overheats it shuts down the alternator... . you slow down, find some place to stop all this time the thing is cooling off... . and when you restart its charging again...

I guess one of the things I might do... is when the charging shuts down, put your hand on the side of the batteries and see if their hot... . I've seen dry batteries that you can touch but not hold your hand on because their so hot... .

Hope this helps. .

 

[MxShawn]

Thanks everyone, will try everything you guys suggested today. . i have a load tester at work ill throw on there. . there is no check engine light, but ill see if i can pull up any codes anyway. . thanks a lot.

 

[ryecreek]

soft codes = no cel

batt temp is a soft code i believe a 0514

 

[MxShawn]

Thanks for the help, load tested the batts at work today. . one is bad. . gonna get new ones tomorrow

 

[Harlacher]

Did the new batteries make it any faster? Want to race that heavy duty for pink slips?

 

[MxShawn]

last week yes we could have raced... . this week no chance. . glad your transmission is in man. . let me get my clutch and we'll play. .