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Adding Fog Lamps to non-performance package CTS

61K views 72 replies 35 participants last post by  redheadedrod 
#1 ·
Has anyone been able to add the fog lamp assembly to a CTS 2008+ that only had the plastic placeholder inserts? Is the fog light wiring there for all cars or is it special for the performance packages?
 
#2 · (Edited)
UNFNick2

I too have been investigating such. I have a 09 CTS 1SA FE1 with no fog lamps and have been reading several articles in this forum regarding such. My goal is to instal the fog lamps and use them as original as possible. I have ordered some parts already (fog lamp assembly x 2 pn 25808666, LH bezel pn 15904574, RH bezel pn 15904575, connector x 2 pn 12085498) but have yet to instal (fog lamps are back ordered). There are other threads that describe instalation with pictures from a user called yourgmsolutions but I have been unable to view them - that's as far as I have gone so far - would appreciate any info you could supply. The original fog lamp switch is part of the signal lamp lever and I haven't ordered that one yet as I am unsure of the correct part number - the one stated in another thread is not correct because when the dealer calls it up it shows part number unknown.
 
#4 · (Edited)
cts2008lover

Thanks, I will try that number on Monday - I believe that is one of the numbers that the parts guy came up with but was unsure of the application with what I was trying to accomplish - Thanks again. Do you have any information regarding wiring up the switch to the relay and fog lamps ? I would appreciate any help.
 
#5 ·
Added left and right fog lamp assemblies, left and right bezels, added combination switch on column and all were easily applied. Can anyone help me to wire these up using original equipment or assist with any pictorial / diagrams to bypass using own wiring but still use column switch. Appreciate any help.
 
#7 ·
UNFNick2
So far its been easy, I haven't taken any photos because of the ease of assembly but I can describe as follows:

parts required - 2 fog lamp assemblies #25808666 - 1 LH bezel #15904574 - 1 RH bezel #15904575 - 4 attaching screws #11589015 - 1 combination switch #25993191. First thing is remove the lower plastic panel by removing 2 10mm bolts and about 10 push pins, that will give you sufficient clearance to remove the spring clip on the inboard tabs both sides so you can remove the black filler panels, just pry the clips enough to remove because you have to reuse them on the bezel, push on the back side of the outboard edge of the black filler to remove the panel, once out remove the two plastic retainers from each filler and install them on the new bezels and install as if it were the filler, use due care not to scratch paint, insert tab first. set the fog lamp assemblies in place on both sides, there are fork like projections that align them in place, finger start the screws into the plastic embosses and secure them with a 1/2 drive 7mm socket, DO NOT OVERTIGHTEN. You might want to do the right side first, its more restrictive. The switch is straight forward - remove the four 7mm screws from the underside of the steering column, gently squeeze the plastic underneath to seperate the covers (3 pieces, 1 top & 2 on bottom) I only removed the outboard bottom to gain access, gently squeeze the release tabs to remove the switch (I used 2 small screwdrivers), remove the two connectors and add the new switch (make sure you apply the connectors straight into the receptacles to ensure good contact) then reverse the procedure to reinstall. A good way to check for function is to test the switch by turning the fog lamp switch on and off noting the tell tale lamps on the right side of the cluster. Now I need help with the electrical SOMEBODY PLEASE !
 
#8 ·
As you know, the required wiring is not on the car. The harness is available but as a complete assembly which means unplugging and plugging everything from the old to the new harness. The fog lights will plug in but you are getting into a huge and expensive project. Your own wiring is probably your best bet.
 
#9 ·
Yes, I am aware that the wiring/fuse/relay are not there and expect to use my own. but what I need assistance with is how to wire the relay and fuse up and use the OEM switch when installed to the steering column. Someone must have done this already and would appreciate some assistance.
 
#10 ·

Attachments

#11 ·
YourGMSolutions relay picture attached. I think others have said the 12v to fog lights has to be wired to low beams if you do not have the factory harness.

Use these pictures at your own risk, I have not done this mod. Just trying help by supplying the missing photos with this and previous post.
 

Attachments

#12 ·
Jumbo - appreciate the photos, I too have not completed this project. What I've done thus far is removed black bezels added chrome replacement bezels, added lamp assemblies as per original equipment. Purchased a lamp harness for KC driving lamps (came with correct gauge wire and relay) and modified it for my situation, soldered and built a harness with proper connectors to the lamps. Ran seperate ground to negative side of lamps. Used relay terminal 30 (20amp fuse) direct to battery, terminal 87 (15 amp fuse) to the positive side of the lamps, terminal 85 to 12v feed from the fuse block using an add a circuit @ the RT LO BEAM as it is not used but tied into the ignition system (10 amp to protect the fuse blk and 5 amp to protect the switch), terminal 86 (haven't completed yet) to the {I think connector x4 terminal 11}. I have already changed out the multifunction switch that has an orange wire @ terminal 7 on the switch that goes to terminal 19 @ connector x1 (light green) at the BCM. What I haven't figured out yet is (because the wiring is not there from the BCM to the fuse blk underhood for the 2009 minus T96) how to pass the wire into the interior and what colour is connector x4 and what is terminal 11 on that connector, where I can order what part number for the pin for terminal 11 and finally if the BCM has to be programmed. I know that the lamps will turn on as soon as I ground the switch wire and it carries 135mA. Still plugging away looking for answers.
 
#13 · (Edited)
OK - I need some wiring help ! I have completed the wiring as per the fog lamp schematic in the service manual. I have added the OEM lamps, the OEM connectors, the OEM multifunction switch, the wiring from the switch to the BCM is already there on the 09 but the wiring from the BCM to the fuse box underhood is not - so I added my own outside the fuse block. The wiring (orange wire circuit 192) goes from white connector pin #7 on the switch to light green connector pin #19 on the BCM, then the wire (dark green/white circuit 1317) goes from black connector pin #11 at the BCM to the relay terminal #86, terminal 85 goes to ignition feed, terminal #30 goes to battery supply, terminal #87 goes to positive side of fog lamp. Under the above condition if you turn on the switch for the fog lamps the telltale lamp on the dash indicates they are on, and if you ground the lamps to a body ground they will be on and indicates they are hooked up correctly. For all this to work the BCM must be programmed to have T96 RPO - BUT my dealer said that the Tech Line will not do a one of change to their software. DOES ANYONE OUT THERE KNOW HOW TO WIRE THIS BY BYPASSING THE BCM SO I CAN USE THE OEM SWITCH - ITS A MOMENTARY SWITCH ON THE SIGNAL LEVER ??
 
#15 ·
cts2008lover
I ran mine in thru from the right side by removing the cabin filter screen under hood and lower under dash cover inside below the glove box. There are 2 grommets - one from the engine side to the cabin filter side and the other into the interior - its tedious and you need patience but doable. I first removed the sealing tape and then fed a stiff plastic band tie thru between the rubber and the wiring then applied a small amount of silicone sealant, let it set up then resealed with the tape one grommet at a time - it took me quite a while but was patient. Before I ran the wire I used shrink wrap around the wire to provide additional protection - maybe overkill but made me happier. I'm questioning attaching to #7 terminal at the switch not being an electrical person - I'm trying to understand. Was your wiring (orange) there from the switch to the BCM?? Was the relay and fuse in the underhood fuse block or did you add your own outside of the fuse block as I did?? Not sure if your working from the vehicle schematic - feel free to send me a private message if you wish - never done that before but hope to figure it out.
 
#16 ·
cts2008lover
Did some testing today - Removed terminal #19 from the light green connector (orange wire from terminal #7 at the switch) and temporarily connected it to the wire from the relay (to isolate the BCM if anything went wrong). When I turned the OEM switch on it no longer latched to complete the circuit but the fog lights did come on when you held the switch on. Put the #19 terminal back into the light green connector and tapped into the orange wire with same results - switch would no longer latch, telltale lamps on dash no longer displayed but fog lamps did come on if switch was held in on position. So, the schematic shows an I/O pull up resistor (+) internal of the BCM at the end of the orange wire and an I/O low side drive switch (+) at the end of the wire coming from the relay. My guess is that these two items need to be built into the circuit to make the OEM work - Does anyone have any idea where these can be obtained?
 
#19 ·
can some one tell me if the chrome bezel p/#15904575 has the hole on the side of the actuallight bulb . heres the problem went to dealer to buy the bezels and the chrome bezel that he brought out had to hole one for the fog light and the oter was just a plain hole , then we went to the show room and the 2011 cts had bulb in one hole and some kind of filler piece inthe other has anyone seen this problem please let me no , dont want to order part and have the bezel without the filler piece thanks .
 
#21 ·
laclac
The bezel does have two holes, one for the lamp and the other for air ducting to cool the brake parts at each front wheel. The ducting is meant for the FE2/FE3 suspension and brake systems. I have the FE1 suspension and did not add the ducting when I installed the fog lamps but did add screening to cover the hole from an accessory supplier just as a finishing touch. I have yet been unable to hook up the lamps using the factory switch but in the meantime have been using a seperate rocker switch - I've explained in previous posts in this thread. If you have any insight to the electrical end, it would be much appreciated.
 
#22 ·
I have been wanting to add fogs to my 2010. Just a thought, if adding the OEM combo switch causes the fog indicator in the IP to light, why could we not use the voltage from that lamp to trigger an external relay, then connect the our fog lamps to this. Would we not have OEM type control?
 
#26 ·
Let me clarify. All I was saying (and I should have said it) is that I'm not mechanically skilled. I don't mind paying someone to do a good installation on it, I just don't want to overpay is all I meant. The last 3 vehicles I've owned have all had them, and they are very useful as I do auite a bit of night driving these days.

That being said, It looks like it may be more trouble than it's worth, but I'll keep looking around.
 
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