Battery light

jtpappy · Sep 25, 2014

I put the secondary alternator I got off Line in because I had to put my duel fueler where the factory primary was. And I am running the battery light and a p09026 code. Could it be on because I am using a 135 amp instead of the factory? Or maybe I got a bad alternator.

Sent from my iPhone using Tapatalk

Jbird · Sep 27, 2014

What is the amperage on the stock primary

Powerstroke Man 6.4 · Sep 27, 2014

Jbird said:
What is the amperage on the stock primary

From the looks of the ford parts website the primary on D A trucks are 200 amps.

Jbird · Sep 27, 2014

And you had to remove your primary so you only have the 135 amp now correct?

Animosus · Sep 27, 2014

1. P09026 is not an SAE code. I tried removing one of the zeros and neither was anything charging related.
2. Check the output at the alternator, see if it is within specs.
3. Battery light is caused by the battery discharging, so you are probably drawing more amps than the alternator can put out.

I guess another possibility is that your signal wire to get the field circuit going is not working, therefore your alternator is not putting out. Make sure everything is wired up right.