Sierra SLT factory fogs install no indicator after BCM pro

dguth66 · August 14, 2020

Hey there ... we had the new truck to dealer recently and one item was for them to activate the fog lights by programming the BCM ... I installed the factory kit as per GM instructions (already wire in pin 10 BCM to C3 ) and I gave them the code sheet. The lights work with low beams only as normal but the fog DIC indicator does not illuminate so in daytime no way to tell. From manual It says the indicator should come on but service guy said there’s was no dictator when we picked it up ??

Noticed something the other day when truck running and just daytime driving light on when’s I select fog# to come on they do and the green headlight on indicator is on or off along with the fog selection.

Anyone have an idea .... seems to me the sales guy said his demo LT had similar issue and they had to reprogram but I’ll have to check.

dguth66 · August 16, 2020

Anyone else have the GM fog kit added and can confirm about the indicator in the DIC would be appreciated

Thanks and cheers !!

316hepster · August 25, 2020

I had the same issue. They tried to tell me it’s supposed to be that way. I had to plead w them to try and flash it again and lo and behold the indicator works now. From what I understand there’s more than one way to do it, the old way and the new way (whatever that means). Keep in them. The indicator should work when the fogs are on.

dguth66 · August 25, 2020

Hey 316hepster thanks for confirming that .. I have an upcoming appointment so I’ll get them to look into it. Appreciate the help ..

dguth66 · August 31, 2020

Ok we got to the bottom of the issue

My dealer did program the BCM (using GM factory accessory light kit code to GM) from the config file GM provided but since my truck did not come with fogs the cluster needs to be flashed as well.

In talking to the Service Manager, he noted one of his techs had same issue before and they had to go back to GM and ask for another file to program the IPC (cluster) ... so with that I'm confident for my next dealer visit things will work as they should.

Cheers ..