Battery light on truck dash
Thread Starter
TECH Junkie
Joined: Dec 2012
Posts: 3,615
Likes: 1,327
From: Iowa
Battery light on truck dash I had the alternator go bad on my truck (01 silverado, 5.3) and had a replacement 99 alternator sitting on the shelf at the shop, so I just swapped it in.
The 01 alternator had 2 wires in the 4 pin plug
The 99 alternator had 1 wire in the 4 pin plug
Now my battery light on the message center is flashing (truck charges just fine, no issues for 3k miles now)
I'm assuming on the 01 that one wire is the ON signal from the pcm to actually engage the alternator charging circuit.
And the 2nd wire is some type of feedback to the pcm or dash or bcm. Not sure.
Short of buying a new alternator, is there another way to get the battery light to stop flashing?
The 01 alternator had 2 wires in the 4 pin plug
The 99 alternator had 1 wire in the 4 pin plug
Now my battery light on the message center is flashing (truck charges just fine, no issues for 3k miles now)
I'm assuming on the 01 that one wire is the ON signal from the pcm to actually engage the alternator charging circuit.
And the 2nd wire is some type of feedback to the pcm or dash or bcm. Not sure.
Short of buying a new alternator, is there another way to get the battery light to stop flashing?
On The Tree
Joined: Aug 2004
Posts: 104
Likes: 2
From: Central, IL
I think the reason is the F terminal on the alternator. I looked at a 99 Silverado flash file and compared it to an 01 flash file. They both have the L terminal, but the 99 didn't have / use the F terminal, and the 01 one does. If you already have a license on your PCM, you can turn this off in the flash file (look under the Vehicle platform options).
