Adding OEM Fog Lamps, Switch

Appreciate assistance

I’m a rookie here and know basics but that’s all – Hopefully I'm in the right area and someone can help me.

I have an 09 CTS with no fog lamps and am in the process of adding them. I purchased and installed the bezels, lamp assemblies and switch – all OEM parts. Under normal conditions if everything was there you would just rotate the switch (part of the signal lamp switch) and it would latch turning on the tell tale lamp on the IP and the fog lamps would illuminate. Now presents the issue – the wiring is OEM from the switch to the BCM but not from the BCM to the fog lamps. I’m trying to bypass the BCM and still use the OEM rotating latch switch. Below is the schematic if the vehicle was ordered with Fog lamps – the red dotted box around the relay in not there. I did try and duplicate it and went to the dealer and they tried to program the BCM but required software on their end from the most famous GM to succeed but their reply was that they would not spend time on a one of case. So, I’m left to try and fend for myself.

I created my own harness as shown and tapped circuit 1317 into circuit 192 but what happens is when you rotate the switch, the tell tale lamp on the dash no longer comes on and the switch does not latch – if I hold the switch in the on position the fog lamps will come on. Can anyone help me work around the BCM and still use the OEM switch so it works like factory. Disregard the right side T79 area.

Sorry for earlier snafue - I guess the rookie part really shows.

Appreciate assistance

I’m a rookie here and know basics but that’s all – Hopefully someone can help me.

Am having trouble uploading schematic so - here goes long way as shown in OEM schematic

From switch is one wire circuit 192 to BCM (live once ignition is on) switch requires power to latch

other side of BCM one wire goes to relay terminal 86

terminal 85 goes to 12v ignition

terminal 30 goes to battery

terminal 87 goes to positive side of fog lamps

If all is normal when yo start the vehicle and turn the rotating latch switch for fog lamps to come on, the tell tale lamp on the dsah illuminates, and makes a switch in the BCM go to ground and illuminates the fog lamps providing you can program the BCM for that option BUT I can't. So I need a work around - any help would be appreciated

Thanks for the quick reply

It is one style switch - why it didn't hold is when I connected the postive lead from the fog lamps to the switch itself bypassing the BCM the switch no longer held the on position.

You rotate the switch to turn them on and you repeat the process to turn them off - I think you call it a rotating latch switch. I'm trying to upload a schematic but am having trouble doing so.