Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Buick LaCrosse Electrical/Lighting Problems



  • gmcustsvcgmcustsvc Posts: 4,251
    Hello Richard2456,
    Have you experienced the concern again after that day with your dashboard? Did you touch any of the circuitry when you changed the battery in the key fob? Have you had the vehicle diagnosed for the concern? Thank you,
    Mariah GM Customer Service
  • Thanks, Mariah!

    It happened twice, both times near the end of a 400 mile trip yesterday (about half an hour apart) but not since.

    I probably did touch the circuitry in the key fob ... the thing nearly fell apart when I pulled out the old battery ... this happened yesterday as well and now it doesn't work at all.

    No, I haven't had the opportunity to take it back to the dealer. All of this happened late yesterday. The dealer I bought the car from (and who is about three blocks from my home in rural Texas) no longer supports GM products and the nearest dealer is half an hour away.
  • gmcustsvcgmcustsvc Posts: 4,251
    Hello Richard2456,
    What I could do is have an agent look at your situation further for you. The agent will require that you take the vehicle to the dealership to have the vehicle diagnosed. If you would like to me to proceed with this I will need your contact information, dealership, VIN, current mileage and best time to contact you. You can get my email by clicking on gmcustsvc. Thank you,
    Mariah GM Customer Service
  • Did you ever resolve this problem? I'm having the same issue on my 05 Lacrosse now and I'm wondering if I should just replace the relay myself.
  • I had this EXACT same issue on my 2007 LaCrosse back at the end of August. End of a long trip all of a sudden all the dashboard lights come on, cruise control dies, a/c compressor turns off. Radio stays on, a/c works after blow is turned off/back on.. cruise won't work for 10-15minutes.

    Did you ever get a solution to your issue?
  • e_net_ridere_net_rider Posts: 1,380
    With so much electronic control and what appears to be related problems, I wonder if proper antistatic measures are used at all times. Semiconductors are quite reliable until they are damaged by a spike. At that time they may just die, or have a tiny hole blown in the material. This hole will be a point of leakage of current and will grow with time and eventually show as a failure. Often cycling power off and back on will temporarily fix the issue at hand. Heat will cause the problem to resurface more quickly. Heat is also produced at the hole where unwanted current is flowing. When troubleshooting to locate a specific component such as a chip a couple of thermal techniqes often aid. At the moment of failure, check for hotter than normal components. Also spraying with a product called cold chill, which was a type of freon, nonconductive, would often induce the part to start working again until it warmed. This would not be practical most of the time because of not being able to access internal parts of computer boxes.

    Static is not the only enemy. Electro-mechanical induced spikes and surges can have the same damaging effects.
    Olds Auroras and likely Buick Rivieras of same period had a safety problem addressed by TSB. There were no diodes on the cooling fan motors to stop inductive spikes when they were energized or de-energized. It said that this was causing failures in BCM and anti-lock brakes. The fix was very simple and took about 10 minutes. Sadly, 09 Malibu had similar issues because of having left the same diode out. Fix was the same. I can tell you that mine did not have the diodes but the VIN was not included for the fix.
    It probably would never have surfaced if it had not been a safety issue, anti-lock brakes. But the lack of those diodes can damage any electronics that are not designed at extra cost to withstand such. Damage often hits the weakest component which likely exceeds design standards. If it gets your radio, probably not safety issue. It dies after warranty, you buy it.
    As of yet, I have not received from GM an explanation as to why mine does not have diodes.
  • I have a 2011 LaCrosse CXL that is doing the same thing. I've had it less than a month and it is heading to the dealer for the third time. I hope that they can fix it soon.
  • donegaldonegal Posts: 49
    My 2010 LaCrosse CSX with 10,000 miles on it had a similar headlight problem the other day. As I started the car a message appeared on the dash that the left low beam light was not working. I checked and sure enough the low beam was not working. I used my high beams to travel to my destination. When I started the car to return home the headlights worked fine. Will report it to dealer at my next service appointment.
  • e_net_ridere_net_rider Posts: 1,380
    It will be nice if someone figures out the root cause.
    I see someone had BCM replaced which brings to mind another high tech vehicle.
    On that one a common problem was with the switch on the steering column. It was mechanically connected to the left combination stalk. The lubricant inside the switch would get gummy and make multiple contacts stick and your vehicle would behave like it was posessed. No one around and lights would start coming on randomly and flashing. Sometimes it was accompanied by horn. Those who did not get the horn often found a dead battery. The BCM was sometimes misdiagnosed as the cause with the problem later showing up again.
    Not to jump forward too much, there are symptoms of other issues here as well.
    A single light would behave as described if the filament is blown. They sometimes re-establish contact and all seems fine, for awhile. Several times I checked bulbs to find they were working, but often too dim at night so it seemed. Once I discovered the bulb was actually out, I started disassembling and it came back on. Fine for awhile. I had assumed the connector was not solid. Next time I removed the bulb and pysically looked closely at filament. I tapped it against my palm a few times and it freed itself so I could see the break. No further problems with headlights or daytime running lights after I replaced those bulbs with newer brighter. Until I actually got the Christine effect. A 2$ can of contact cleaner and half hour of time saved me hundreds. If they changed BCM it was hundreds and later discovered it was the switch, then they replaced the harness segment it is soldered to. $400-500.
    Good Luck. Hope everyone still has warranty.
  • We're experiencing this same problem. This is definitely a safety issue since the lights go out on low beam. If we're on a lighted street, we do not notice it. Did this rectify your problem? Thanks for your input.
  • Was your problem with the lights finally rectified? Thanks for your post.
  • I have this same problem on my 2006 CXS. The low beams just go out for no reason. brights work fine. I drive with the fog lights on all the time at night so that if the lights decide to go out I still have some lights without having to use the brights. The lights seem to always come back on after a few minutes. I have started to turn the lights off and let car idle for a few minutes prior to leaving the house, then turn the lights on manually and drive with the fog lights on. Its worked for the last few times I drove at night, but I may be fooling myself. I am going to purchase an Exterior Lighting Relay and replace it.
  • Yes, our problem with the lights has not happened again since replacing the Exterior Lighting Relay. It has been nine or ten months since replacing the part. This is about a $25 part. Sorry, I didn't see your message when you posted it. Hope this helps !
  • Thank you very much. I am going to pick up one today and replace.
  • Hello Mariah,

    I just called a local dealer asking for the Exterior Lighting Relay and he tells me that he could find a relay with that name. I dont know if you have access to the part # or if you even know exactly what we have been posting about, but I would appreciate it if you could locate the part # and send to me so I can get it from the dealer and try to prevent the problem from happening again.

    Thank you,
  • gmcustsvcgmcustsvc Posts: 4,251
    My name is Christina; I have taken over for Mariah. What dealer are you working with? Can you please email me with your VIN and current mileage? I am working to find an answer to your question. I look forward to your email.
    GM Customer Service
  • Hello Christina,

    Thank you for getting back to me. Here is my VIN 2g3we587461287233, mileage is 74K.
    I am not currently working with a dealer, although I have worked with Jerry's in Weatherford, TX on other issues while the car was in warranty. This issue did not come up during that period.
    Thanks again. Phil
  • I looked up my service record. The exterior lighting relay was replaced on 5/29/09.
    We have not had the problem since. Our car is a 2006 LaCrosse CX. The part number for the relay that was installed is: 15016745 . Hope this can help !
  • Thank you very much!! This is great, I will call the dealer and see how quick I can get one. I have an 06 CXS. Thanks again!!
  • gmcustsvcgmcustsvc Posts: 4,251
    How did things go getting your vehicle fixed? I look forward to the update on your progress.
    GM Customer Service
  • jack0059jack0059 Posts: 2
    I am installing a after market backup caqmera. I want to hook to the backup light inside the trunk. I have found 6 wires. Black/yello stripe,Large plain black, small plain black,Green/right stripe,blue whright stripe, puple/wright stripe. Can anyone idwentify whick ones are the backup lights? I got little to no help from my dealer.
  • jack0059jack0059 Posts: 2
    2011 Buick Lacrosse
    I am installing a after market backup caqmera. I want to hook to the backup light inside the trunk. I have found 6 wires. Black/yello stripe,Large plain black, small plain black,Green/right stripe,blue whright stripe, puple/wright stripe. Can anyone idwentify whick ones are the backup lights? I got little to no help from my dealer.
  • philp433philp433 Posts: 6
    Hello Christina,
    I purchased the relay suggested by amkdevile in his post and found it was the exact relay used in my car. It is listed as fog lights in the fuse panel. At the suggestion of the dealer, I did not install it but repositioned it with another relay in the panel (A/C). So far the A/C has worked and the lights have only gone off one time for about 10 seconds. I may go purchase the relay if the lights continue to go out, thinking that the new relay may be built with some better components internally now than the originals were. However, that may be dreaming. The frustrating thing is that the car runs great, most of my driving is daytime so on the occasion the lights do go out it may have been a month since I have driven it at night for any substantial amount of time and am not expecting anything to go wrong.
  • gmcustsvcgmcustsvc Posts: 4,251
    Please let me know if you need anything else or if your concerns return.
    GM Customer Service
  • alchipalchip Posts: 18
    We love our 2006 LaCrosse, but we have had this same problem for months (just happened last night.) Like the other folks said, the manual override surprisingly does not work (i.e. taking it off AUTO and moving it to the manual low-beam setting.) To me, this is quite dangerous. Thanks for the other posts - I'll try replacing the relay.
  • amkdevileamkdevile Posts: 19
    I looked up my service record. The exterior lighting relay was replaced on 5/29/09.
    We have not had the problem since. Our car is a 2006 LaCrosse CX. The part number for the relay that was installed is: 15016745 . It might be called fog lamp relay ( Day time running lights ).Day time running lights don't work when we were having the same problem. Hope this can help !
  • alchipalchip Posts: 18
    Super. Thanks so much, I'll give it a whirl!
  • jj17jj17 Posts: 1
    i have looked at some of the solutions. one was a relay under hood with a number on it of 8866/1532866. i found it, however i have at least four of these relays with that same number.

    someone else said part # was 1501675. in the fuse box under hood what number is it. 35,36, 37 etc based on diagram in owners manual, any help would be great.
  • spicoli2spicoli2 Posts: 6
    This is most likely due to a faulty HDM Module (Headlamp Driver Module). It can be located in the fuse panel on the left hand side of the engine compartment to the left of the fan belts, it will be location #35. These are common problems on 2005-2007 Buick Lacrosse model years. You can get one at the dealer for $48 or an aftermarket version at Advance Auto Parts for $35. The part number at Advance is R6100 and it cross references with GM part number 15016745. I'm sure other auto parts stores will have these as well, you will need to check with your local store for availability.

    These are simply plug and play with no technical aptitude needed. Make sure the car is off and remove the old module and replace with the new.

    FYI- if you are going to check for day time running light operation, the car must be placed in drive before those will come on.

    Hope this helps!
  • I also am having the low beam headlight problem. I tried switching the relay with the AC relay. That seemed to work for a day or two. Sometimes the lights come on during a trip but usually not, then the next time the car is started, (next morning), they work fine again. I am leaving on a trip tomorrow and would love to resolve this problem before then!
Sign In or Register to comment.