I heard from my girlfriends dad (a man that seems very knowledgeable) that if I were to install the harness that I could possibly fry all my electronics (ECU and such) due to feedback if the one way relays fail. Is this true? Whats the chance/risk? Somebody please help Im confused

 

Never heard this before. I fried my OEM one's 3 or 4 times by putting in higher watt bulbs and it never killed my car.

Erik

 

I am not a complete expert as I think it depends on the relay, but if it is one way and it fails I am pretty sure the headlights will just fail to turn on. . . Also, the current is only flowing one way and I can't think of a way that it could be sent the opposite direction, although I may be corrected on this. I have never heard of anything bad happening to the electrical system due to an upgraded harness, although the one I bought fried within a month with 85W bulbs, so I just bought Piaas.

 

I really need hard evidence guys if Im going to install it cause I have to explain to him that it would not hurt the electrical system one bit. Unless of course it would then thats a different story.

 

its funny that your handle is lightboy, just ironic.

 

Where is he getting this from? Does your girlfriends dad also work for firestone tires? I dont think it will cause any damage but id like to see any proof he has that it will because half of the board might have to take theres out.

 

Ask him what could drive current the opposite way through the relay? The lights aren't a current source and therefore it would violate Kirchhoff's current law if it flowed the oppostie direction, for those that don't know it states that the algebraic sum of the currents entering any node is zero, nothing could be damaged if a relay failed unless a capacitor was somehow added, but that isn't happening (and no stereo caps. added to the car won't affect this situation either.)

 

Why do you have to prove anything to your girlfriend's dad? Just get it, install it, and use it with no problems...that will prove it to him...

 

that's stupid... there must be 100s of people here who have been using them for years. I would love to hear his technical reasoning.

 

Hmm I think your girlfriend's dad is misguided.

Read up here
http://www.howstuffworks.com/relay1.htm

The APC wireharness have normally open relays which means if they fail all that happens is your lights won't turn on. Plus how can they provide feedback to the ECU? The only connections the wiring harness makes is to the battery and the headlight socket.

First off there is no way it can provide feedback to the battery (since it's the source of current), so that's out of the question. Second if it somehow sent current back through the headlight socket, you'd blow a fuse in the fuse panel.

I have a pretty good grasp of electronics and electrical systems. It's my degree (BS Electrical Engineering) and my job.

 

As long as it works right. It
s cool with me....
Hold on, wire harness, yeah I had a faulty one in my old car. Caused my stereo to get friend. A guess that what happens when water seeps into the speaker from the outside. I really don't think wire harness's that handle more wattage can do that type of damage.

 

Sorry guys didnt mean to get you guys all worked up. I talked to him today and he retracted what he said. The whole reason it came up was I asked him if he would help me (you know anything I can do to get on his good side).


yeah I like lights hence the name lightboy, too bad Im just a poor high school student that cant afford HIDs. Well maybe I need to start dealing again ( JK!!!)

 

In the relays of the APC harness, any power surges would only serve to pop a headlamp fuse and relay. There's no chance that the surge would make it way to your ECU.

 

Installed the harness today man it made my light look clean! They are like superrrr white now. Thanks guys