2015 Silverado 5.3 LT shows P129D even after new fuel pump module and battery?

[greenoliver1]

My truck will throw the P129D every couple of days when I start my truck, code never comes up driving. I’ve installed a new fuel pump control module, and a new battery, and the issue still persists. Anyone else had this issue before? It’s got me confused

Edited October 19, 2021 by greenoliver1
Added to post

[silveradosid]

watch this video 

 

[greenoliver1]

On 10/19/2021 at 8:53 AM, silveradosid said:

watch this video 

 

i watched the whole thing, but the problem is in Eric’s case the code was staying no matter what, if I clear mine it goes away for a few days then randomly comes back when I start my truck. If mine was constantly on I could easily do the same procedure for finding the break, but I checked my whole harness as best as I could and didn’t see any chafes, and I opened the harness in a few spots and tugged the wire hoping it was broken and would come out, but it was nice and tight in there 

[silveradosid]

it still could be the problem, it may not be corroded all the way threw and the plastic wire insulation will be strong enough that you cant pull it apart. does moisture or rainy days seem to effect when the light comes on

[dlopez]

On 10/22/2021 at 5:19 AM, silveradosid said:

it still could be the problem, it may not be corroded all the way threw and the plastic wire insulation will be strong enough that you cant pull it apart. does moisture or rainy days seem to effect when the light comes on

Hello. Did you find the cause to the problem?

Thanks

[dlopez]

My 2016 gmc sierra just stared doind the same thing. Same code. Did you solved theis problem?