My battery light keeps comming on and off while the truck is running, this happens after putting on a new belt any idea what might be wrong. Is the belt to long maybe? I have a 200amp alt and eletric fans, and a small amp for 1 sub and 2 6x9's.

 

If you alt is not factory it probably doesn't have the right regulator to communicate with the PCM. As long as your voltage is ok then you can have the battery light turned off in the tune.

 

The regulator could be bad. Does it come on and off if you hold the idle at 800 or 1000 rpm's? If the light goes off holding that idle, then the idle may need to be raised. If the idle is already set correctly, then you may need to get a different alt pulley to raise the alt rpm at idle. Is the problem just at idle? I should have asked that from the beginning. Why not just use a O.E. 145amp alt? With what accessories you are using, the 145 amp alt should be more than adequate. IMO

Jim

 

You can disable the L and F terminal codes in the pcm, thatll take care of that! I had to do it when I changed from a 99 to an 01 pcm.

Chris