I installed my 120 yesterday and have been having a weird problem. I have a 2007 tahoe and when the automatic headlights turn on the unit pretty much becomes useless. Audio hardly plays from any source, meaning the volume could be set to 30 and there is just a slight wisper audible. When I turn the volume up, the volume doesnt change, however a minute to two minutes later it will respond and turn the volume up super loud. It also seems to disconnect from the sub as there is absolutely NO bass at all when this is all going on. To fix it I have to shut the truck off and turn it back on, in which case it all works again without problems. I cant figure out what the deal is....might disconnecting the illumination/dimmer/whatever it's called wire solve this, so the unit just doesnt know when the lights are on or off?

Thank you again for the help!

Do you have H.I.D. head lights on your vehicle?

Yes, Philips HIDs.

How did I know? Let me guess you have them wired straight to the battery with a relayed harness as well right?

Yup. Do you have a solution to this fix that doesn't involve removing the lights? Thanks.

Remove the relay and connect the H.I.D.s directly to the car's headlight harnesses. This will eliminate your problem and this has been the solution for many people sense I started suggesting this when I had a similar problem a year ago.

Remove the relay and connect the H.I.D.s directly to the car's headlight harnesses. This will eliminate your problem and this has been the solution for many people sense I started suggesting this when I had a similar problem a year ago.

Vblue, you might have already answered this question but I dunno... I tried searching but couldn't find it... ok so

My question is how did you know EXACTLY what his problem was?!!11

Remove the relay and connect the H.I.D.s directly to the car's headlight harnesses. This will eliminate your problem and this has been the solution for many people sense I started suggesting this when I had a similar problem a year ago.

Thanks for the help. The front passenger side HID is plugged into that side's harness. It then goes through a relay and goes to the other ballast/light, bypassing the driver's side headlight harness. I'm not sure there is any other way to set the HIDs up? Is there anything with wiring in the dash behind the unit I can do to fix this? i.e. cut the dimmer/illumination wire?

Is there anything with wiring in the dash behind the unit I can do to fix this? i.e. cut the dimmer/illumination wire?

Well there might be but as far as I know with every post similar to this one, the only suggest that has fixed everyones problem is to eliminate the relayed harness. Most H.I.D. systems come with both types of harnesses. If yours did not, I would suggest doing a Google search for an H.I.D. harness for your type of vehicle or contact the manufacture of the system you have.

Vblue, you might have already answered this question but I dunno... I tried searching but couldn't find it... ok so

 

My question is how did you know EXACTLY what his problem was?!!11

 

Yea I covered this back a year ago when I had the problem but I probably couldn't find that thread if I tried. The way I discovered this issue was interesting. I had my H.I.D.s wired without relayed harnesses for over a year and with the Z installed without issue. I then had projector retrofits made for my car and decided to incorporate the relayed harnesses when I installed the new headlights and immediately started getting this problem. Sense I new the last thing I changed was the relayed harnesses I had a good idea what was causing the problem so I went back and eliminated them and the problem went away for good. Literally less then 24 hours later two post showed up on this forum describing the same issue. I inquired as to their H.I.D setup and all had relayed harnesses. I suggested eliminating the relays and their problems went away as well. Over the last year or so this has come up about once every couple of months and it is always the same issue and solution. This has become so common now that I can pretty much at this point not even ask people if they have relayed H.I.D.s and know that is the problem. I would like to know what is actually causing the problem though to see if there is another solution that good be worked out.

Is there anything with wiring in the dash behind the unit I can do to fix this? i.e. cut the dimmer/illumination wire?

 

Well there might be but as far as I know with every post similar to this one, the only suggest that has fixed everyones problem is to eliminate the relayed harness. Most H.I.D. systems come with both types of harnesses. If yours did not, I would suggest doing a Google search for an H.I.D. harness for your type of vehicle or contact the manufacture of the system you have.

Mine only came with the one harness. I'm not entirely sure what the new/different harness should be/look like as I have never dealt with this before. Here is a link(http://www.philipsxenon.com/philips-bulbs-ballasts-wiring-upgrades-c-380_383 to the two harnesses available from Philips for my lighting system. Would you be able to tell me which of those I need? Thank you so much.

Edit: I should also mention I had the same lights/setup with my z3 and never had the problem.

Vblue, you might have already answered this question but I dunno... I tried searching but couldn't find it... ok so

 

My question is how did you know EXACTLY what his problem was?!!11

 

 

Yea I covered this back a year ago when I had the problem but I probably couldn't find that thread if I tried. The way I discovered this issue was interesting. I had my H.I.D.s wired without relayed harnesses for over a year and with the Z installed without issue. I then had projector retrofits made for my car and decided to incorporate the relayed harnesses when I installed the new headlights and immediately started getting this problem. Sense I new the last thing I changed was the relayed harnesses I had a good idea what was causing the problem so I went back and eliminated them and the problem went away for good. Literally less then 24 hours later two post showed up on this forum describing the same issue. I inquired as to their H.I.D setup and all had relayed harnesses. I suggested eliminating the relays and their problems went away as well. Over the last year or so this has come up about once every couple of months and it is always the same issue and solution. This has become so common now that I can pretty much at this point not even ask people if they have relayed H.I.D.s and know that is the problem. I would like to know what is actually causing the problem though to see if there is another solution that good be worked out.

Was a rhetorical question that was meant to be satirical

Oh! Yea sometimes I don't get it. I am sure some people are actually thinking this however.

Oh! Yea sometimes I don't get it. I am sure some people are actually thinking this however.

You punk that's why I included the pic

ANYWAY. Back on topic.

Mine only came with the one harness. I'm not entirely sure what the new/different harness should be/look like as I have never dealt with this before. Here is a link(http://www.philipsxenon.com/philips-bul ... -c-380_383 to the two harnesses available from Philips for my lighting system. Would you be able to tell me which of those I need? Thank you so much.

You can try the following forum here:

http://www.tahoeforum.com

Other then that maybe try a google search for an HID harness for your vehicle.

You punk that's why I included the pic

I should also mention I had the same lights/setup with my z3 and never had the problem.

Yea clearly these manufactures have been making adjustments to the power requirements of the units. I have had an even stranger issue with my Kenwood that had myself and several veteran installers completely baffled. It too seemed to be related to certain power requirements that the unit had. This one took me almost a month to troubleshoot and find a solution to.

Mine only came with the one harness. I'm not entirely sure what the new/different harness should be/look like as I have never dealt with this before. Here is a link(http://www.philipsxenon.com/philips-bul ... -c-380_383 to the two harnesses available from Philips for my lighting system. Would you be able to tell me which of those I need? Thank you so much.

 

You can try the following forum here:

 

http://www.tahoeforum.com

 

Other then that maybe try a google search for an HID harness for your vehicle.

I appreciate that I need a different harness, I just am not sure what type of harness you are telling me I need/how it differs from mine. Am I looking to plug both ballasts into each factor harness? If I understood what exactly the harness changes from what I have now, I could go to google and get it sorted....sorry for the confusion, I have only ever dealt with Philips xenon kits meaning I have only ever used one type of harness.

Am I looking to plug both ballasts into each factor harness?

Yes. Most H.I.D. kits you buy allow you to specify what vehicle you have and provide a harness to plug into the vehicle harness for true Plug N Play. Now, most of these kits are cheap pieces of crap bough off of ebay but some high end kits also offer this option. I use NOTTO SE H.I.D. systems and have had excellent results.

Am I looking to plug both ballasts into each factor harness?

 

Yes. Most H.I.D. kits you buy allow you to specify what vehicle you have and provide a harness to plug into the vehicle harness for true Plug N Play. Now, most of these kits are cheap pieces of crap bough off of ebay but some high end kits also offer this option. I use NOTTO SE H.I.D. systems and have had excellent results.

Thank you. The Philips system I have is most definitely not cheap crap (same lights/ballasts bmw uses, although I'm positive the harnesses are sources from someone else). I will check out notto and see if they have a harness system that allows me to fix this. If I used a 50w resistor would I be able to skip the aftermarket harnesses and plug the Phillips ballasts into the factory harness? Sorry for going beyond the spectrum of this website, but you seem to be very knowledgeable and also have prior experience with this exact issue.

I do appreciate the help and apologize if I have come off as a noob.

Thanks again guys.

If I used a 50w resistor would I be able to skip the aftermarket harnesses and plug the Phillips ballasts into the factory harness?

I am sorry but that goes beyond my knowledge. And while we have had this thread going I have done many Google searches to try and find a harness for you and have come up empty as well. In fact, Notto may no longer be offering dual harness options with their kits. PM forum member 1loudls and see if he has any insight into another solution. He is one of the most knowledgable installers on this forum.

If I used a 50w resistor would I be able to skip the aftermarket harnesses and plug the Phillips ballasts into the factory harness?

 

I am sorry but that goes beyond my knowledge. And while we have had this thread going I have done many Google searches to try and find a harness for you and have come up empty as well. In fact, Notto may no longer be offering dual harness options with their kits. PM forum member 1loudls and see if he has any insight into another solution. He is one of the most knowledgable installers on this forum.

Thank you again for your time/help. When I get it sorted, I will make sure to post the fix in case any other gm truck owners run into the same problem.

You maybe exceeding your alternator's output.

You maybe exceeding your alternator's output.

Very well could be, being a GM.... They always underrate their alternators....

You can upgrade a higher amp alternator fairly cheap, by grabbing a Escalade or Denali's alternator from NAPA...

Of course, it would be much cheaper to just wire the HIDs to the original light sockets....

The problem is the spike of ac power coming from the lights as they turn on creating noise that then messes with the unit. Working with an electrical engineer and veteran car audio installer today, we found a fix that doesn't involve altering or messing with the HIDs, the unit, or harness at all and takes about 60 seconds to do if you have the correct parts. We will be making a number of the fixes both for our audio shop and to sell online for $20.