Cadillac STS Forum - 2005 through 2012 Discussion, High-Beams Not working in Past Cadillac Vehicle Discussion; Hello,
Quick question that I hope is very simple My high-Beams are not working in my 2007. Now I have ...
Quick question that I hope is very simple My high-Beams are not working in my 2007. Now I have not checked fuses and should do that as well. I can't help wondering if this is tied to my battery dying a week ago. I didn't drive my car for almost three weeks but everything was working before that. A little strange.
Those fuses only apply to vehicles that do not have IntelliBeam. The relay for IntelliBeam controlled high beams is located inside the vehicle within the instrument panel. There are no relays under the hood for your application (assuming you have IntelliBeam). Cars with IntelliBeam have the relay and fuses present in the fuse block for both applications.
I'll take a look inside as well. Not sure where that is at in the vehicle, but this car does have the I-beam for sure. I played with it a lot at first then found it was coming on when I really didn't need it. Cool feature though when traveling.
Before you go digging I'll post a picture. It is not at all where you might expect it to be.
With IntelliBeam, the high beams also dim/brighten depending on what speed you are traveling. This feature is controlled by the Inside Rear View Mirror. It receives information about vehicle speed and controls the high beam relay directly (which is why I suspect they've located it where it is).
It's wrapped in foam tape in the wiring harness to the left of the radio.
Is there any chance that perhaps both high beam bulbs are bad? You mentioned that you don't really use them a lot and I was just thinking maybe this happened and you didn't realize. Also, are the functions of your ISRMV working correctly?
Just trying to figure out the angle of your photo... Is that on the right side of the dash? I see the white tube which draws in ambient air for the climate control system but I'm having a hard time relating to it. I have a 2008 so there may be a few differences, but I'm confident the IntelliBeam is the same 2007-08.
The easiest is to remove the radio and it should be attached to the harness between the steering column and where the radio sits.
I guess its possible to bulbs are bad but I thought highly unlikely that they both are out. This is a picture from the drivers side above the gas peddle. Not sure about pulling to radio out for this but if its the relay I do want it fixed.
You shouldn't need to unwrap anything to be able to see it, but I think it's further back toward the radio than you can see from that angle.
It's king of a tough spot because it is difficult to access, but so are the headlamp assemblies. If you can get to the relay, you can at least measure the voltage at the relay socket to determine whether the problem is before, at or after the relay. I suspect this is still going to be a little easier than accessing the connectors that plug into the headlamp housings to measure there.
The Red/Wht wire is supply voltage into the relay. If you have no power here (it should be live all the time), then there is a problem between the fuse block and the relay. The light green wire is the feed to the headlamps. With your high beams on, there should be power at this light green wire.
Also, if the fuse is blown for your rear view mirror, or it is not working correctly, this will inhibit the operation of the high beams as well. I'd check your mirror for correct operation as well.
I agree that the likelihood of both high beam bulbs being out is fairly low, but I have seen that before too. Certainly not the highest on my suspect list.