HID questions
- Thread starter IAFF78
- Start date
Blckshdw
Moderator
MAY03LT said:
That would explain why there was no voltage at the pink/white wire at his DRL killer install
I have the foggiest idea how to test for ground with my battery tester. Its the old school radio shack tester with the needle. To test ground do I put the black wire on a hot and take the red wire and find the ground? Prolly sounds like a dumb idea...lol
I've never scoped it, but I thought it was a high-true PWM signal, since the FET in the relay was an enhancement-mode device. A high signal on the control wire makes the output conduct from 12V like a relay closing.MAY03LT said:
In any event, Pin 2 needs to have 12V and it doesn't. Kevin, if you're not sure how to use the meter, get local help and buy them some beer.
All I kkow is red wire to hot and black to ground. I had a digital volt meter but I fried it cause it was on the wrong setting I believe 
Boricua SS
Member
just outta curiousity... how the hell did all this happen just by trying to install HID's? sorry about your luck man...
sucks you have/had to go through all this Kevin.. i remember you saying you had bad experiences the first time around with HID's and now this...
sucks you have/had to go through all this Kevin.. i remember you saying you had bad experiences the first time around with HID's and now this...
the roadie said:
I don't think I've ever ran across the theory of operation of the HDMs. In the "fast" version of the HDM input test, they want you to hook a test light up to 2 and 5 and turn on the headlamp switch to verify power at 2 and signal at 5. In the HDM input testing vid I made, 5 did test for ground with the switch on.
And yeah, this isn't related to Kevins current problem of no power at 2.
Boricua SS said:just outta curiousity... how the hell did all this happen just by trying to install HID's? sorry about your luck man...
sucks you have/had to go through all this Kevin.. i remember you saying you had bad experiences the first time around with HID's and now this...
The first set of HID's were put on my 02 TB back in 2003. That was before all the DRL mods and beefed up wire harnesses were thought up. Or at least before it was widely known as ways to solve the problem. From what i was told, the DRL's fried my ballast after about a year and change of use. Those ballasts were like sherman tanks. Big, heavy and solid. They took a beating for a long time. I wish i could remember which brand it was. I do remember the box it came in was red/black/white with all chinese on the outside. They were fresh off the boat.
There has been a few come to jesus talks during this whole process. Nothing i do goes smoothly when it comes to my TB. Theres only 2 things i can think of that could have caused this. 1. I cleaned the motor 3 weeks ago but i used the water sparingly and only on a fog pattern. I'd say 2 gallons total. 2. When i was hooking the wire harnesses power wire to the battery i had a few sparks when trying to thread the positive back in.
The part that baffles me is the night before i started this endeavor, i took the dog out to the park and the lights worked that night. I did notice after about 6-8 minutes of use, the pass side HID went out. Turning the headlight knob off and on fixed the problem but only for another 6-8 minutes. I figured it was a bad ballast or maybe because i didnt have the wire harness hooked up yet. Now, i cant be 100% sure but i dont remember the light going out until after i did the DRL killer mod. Also i never had a chance to have the truck out in the daytime to check to see if the mod worked. When i did the mod it was evening by the time i finished it. The next day i worked and my truck was parked all day and night so i never had the chance to drive it in the sunlight. The following day is when i did the mod and it was in a garage and when i finished up it was like 445pm ish.
I just dont know how the lights worked right before i started this project and the end results were me having no low beams what so ever. EPIC FAIL.
On a side note, to all that have helped me through this and given me advice, if your ever in south central PA or North central MD, look me up. I owe you guys dinner and a cold one after dealing with my non mechanically inclined a$$. I cant offer any of you sound mechanical advice but I was a professional Chef for 13 years before I made the switch to career firefighter. If you need any cooking tips/recipes or whatever, I will return the favor.
Again, thanks for the solid advice and if anyone has anymore ideas as to how I F'd this up, Im all ears.
Master Electrician Kevin
Boricua SS
Member
i think ive had a few of those Jesus talks myself with certain things i did to my truck along the way... thank God for my Warranty and extended warranty.. or else I'd be up s#!+s creek without a paddle
hope it all works out for you bro
hope it all works out for you bro
Boricua SS said:i think ive had a few of those Jesus talks myself with certain things i did to my truck along the way... thank God for my Warranty and extended warranty.. or else I'd be up s#!+s creek without a paddle
hope it all works out for you bro
Thanks bro
IAFF78 said:
It has to be a fluke. I don't see anything in this thread (or the DRL kill thread from the weekend) that indicates you caused no power on 2. Even if you inadvertently spread 2s terminals, I would still expect to see 12v on 2s pins, they just wouldn't "bite" the corresponding HDM terminal. I've read a few cases where the fuse block had to replaced (for various internal problems) and nothing was messed with prior to the failure, so I wouldn't say it's totally uncommon.
MAY03LT said:
Maybe its me. When I test the relay what position should the key be in? Actually when I test everything, what position should the key be In?
MAY03LT said:
Sweet vid dude.
I think in the morning I'm going to put everything back together and start over minus the drl killer. After cutting and soldering the wires back there I'm afraid to cut and solder more. They don't leave much wire to play with. And ill probably buy a test light while I'm at it unless the 1970's battery tester is suffice.
Wooluf1952
Member
I don't know if this applies or makes a difference in this situation.
I've read that the older needle analog type volt meters should not be used on computerized systems.
Please don't ask for proof, because I don't remember when or where I read it.
I just remember it was the reason I bought a Digital Volt Ohm Meter.
Is there any truth to this?
I've read that the older needle analog type volt meters should not be used on computerized systems.
Please don't ask for proof, because I don't remember when or where I read it.
I just remember it was the reason I bought a Digital Volt Ohm Meter.
Is there any truth to this?
There is some truth, but it's not that the analog meters can do damage so much. They *can* affect the circuit they're measuring to the point that a sensor reading could change. If it's an engine control sensor, that could have bad side effects. Much better to get a good scan tool that can read sensor data using the PCM's measurement circuits. Or a decent DVM.Wooluf1952 said:
IMHO, it's test LIGHTS that have the capacity to do the most damage. Cheap-ass tools in the hand of untrained users are a bad combination. In the hands of someone using them for lighting and switch circuits only, they can be useful. But the very people who need to know the difference are the ones who will not. I almost always advise against owning a test light, but I know they have their fans.
the roadie said:
I will go out in the morning and buy an inexpensive digital multimeter. Not worth buying a expensive one cause christ knows i can barely use one as it is. I do remember that when i'm testing a vehicle electrical current i want to be on 12V DC, correct?
When i retest everything over again, when do i turn on my headlights, car...etc? When i did my tests today every test i did was with the car off, keys on the floor and headlight switch turned to auto on.
So i probably gave you guys some false info and i didnt even know it. So when i test fuses it doesnt matter if the lights are on or the cars off?
When i test the 46 relay i should follow MAY03LT's video but with using the DVM? When i tested it with the analog meter i didnt have the car on or the lights on
How and when should i test for ground when doing my tests?
I wanna figure this out and learn something along the way.
Please bear with me,
Kevin
As i was having my last smoke for the night something had me puzzled. When i tested the plugs that attach to the headlight selector switch, it was showing i had power coming into the plugs. Where is that power coming from? That voltage has to be coming from somewhere and i cant believe its coming right from the battery. I would think its passing through something before it gets there. I dont know if this helps you guys troubleshoot my problem.
Many thanks,
Kevin
Many thanks,
Kevin
Wooluf1952
Member
The free DVM I got from Harbor Freight has a 20 volt DC setting.
I believe that's the best setting for our 12v systems.
I believe that's the best setting for our 12v systems.
IAFF78 said:
The only one that needs the switch on for testing is #5 (on, off, on, off was the headlamp switch being turned on and off). 2 and 6 are constant regardless of switch and/or key position.
IAFF78 said:
It really depends on the circuit(s) being tested. In our headlight circuits, for instance, fuses 3 and 6 don't get power until the HDM pin 4 is energized.
IAFF78 said:
With a meter, connect the positive lead to the positive battery terminal, and use the negative lead to test for ground.
In this pic, the meter is hooked up that way, you just can't see the positive lead. The meter shows 12v when ground is present.
Does anyone have an idea as to why I was showing voltage to the plugs that go to the headlight switch but no voltage to the other places i tested?
Blckshdw
Moderator
IAFF78 said:
From the schematic, all of the lines from the headlight switch run back to the BCM or the front fuse block. Depending on the setting of the switch, it will close a circuit and cause a particular function to activate. (turn on the parking lights, turn on the low beams, etc)
Blckshdw said:
I just wonder why the plugs show 12v and the front fuses and relays dont show squat. Where does the power come from that goes into headlight switch?
Blckshdw
Moderator
Blckshdw said:
Got it thanks.
So from looking at the diagram I would guess that the headlight switch gets power from the rear BCM, correct? The rear BCM gets power from the A5 pink/white wire, correct?
That's true.IAFF78 said:
That's not true. The secret is that the BCM is involved in a LOT of other functions, and it is shown on MANY other schematics. To get a total picture of the entire vehicle involves reading and getting a mental image of ALL these connections.
The power input pins to the BCM are shown on these other schematics. A5 pink/white is ONLY used from the BCM to the low beam relay as a control signal.
Quick basics: Electricity can be thought of as a fluid, like water in a hose. Relays are like valves. Turning the handle opens or closes the valve and allows flow. There are four terminals on a simple relay, two are involved with the main power flow, and the other two are involved in the control. Pin 2 on the relay in this case is the main flow input - like the house piping on an outdoor garden hose connection. Pressure should always be there because there's no shutoff valve inside the house in my analogy here. A voltmeter measures electrical PRESSURE, and should be an instrument like a water pressure gauge that doesn't steal any water from the system to make its measurement. That would be like a leaky pressure gauge. Analog voltmeters are just like slightly leaky gauges, and a digital one is much less leaky. A $3000 voltmeter such as I use at work has almost ZERO leakage and is very accurate.
So if you have a pressure gauge (voltmeter) on the INPUT pin 2 to the relay, and the schematic says it's connected to the "B+" supply, that means no matter what position the vehicle switches are in, that there will be pressure/voltage on pin 2. As long as you have the black wire of the meter on a good ground like the black wire or negative side of the battery or the chassis sheet metal (without any paint in the way).
The OUTPUT of the relay is pin 4. That's like the hose on your house outside faucet. If the valve is off, there will be no water flow there. That's measured by the meter as voltage.
The control wire on the relay is pin 5, and that's like the handle on the valve. Somebody has to turn the valve using a tiny bit of energy themselves, but they can control a much larger flow in the main part of the valve, from IN to OUT. You can put your voltmeter on the control pin 5, and see if the BCM is trying to turn the imaginary valve handle, but ONLY if the BCM is powered up, and attempting to do its job. That requires you to have the key on, and the headlight switch in a position that is asking for the low beams to be turned on. Remember, you can have the engine running, the headlight switch in AUTO mode, and if the shift lever is in PARK, the low beams won't be on. To get a valid measurement on pin 5, you have to have the ignition on and force the BCM to command the relay to do its job.
The last pin on the relay is 6, the ground side of the control circuit. The analogy gets a bit confusing here, but the best way I've been able to explain it is that the control side of the relay (usually called the COIL, but this is a special kind of relay that uses a transistor instead of a mechanical coil) needs a place for the control force (current, which is like water flow - a lesson for another day) to drain off to. The BCM is putting a small amount of current into the relay, and like water, it needs a place to drain off to unless you want it to build up needlessly. Having a ground wire on pin 6 provides this drain-off function. In terms of the valve handle analogy, a PERSON is turning the handle with their wrist, but unless they were standing with their feet on the GROUND, their wrist would end up turning their body like an astronaut working in weightless space. Notice how the astronauts always have to have their feet in a platform restraint so they can use tools? Otherwise their bodies would rotate in reverse reaction to how they're turning the tool. The valve-turning wrist force is the same way on earth. The person needs to be standing on the GROUND instead of a ball bearing skateboard, or else they can't succeed in turning the handle. Hope that wasn't too much for one lesson.
Blckshdw
Moderator
For a second, I thought about trying to answer, but figured, best leave that one up to the professionals. 
the roadie said:
So if the headlight switch gets power from the BCM, then why is there no power from the A5 pin at the BCM?
I picked up a digital multimeter and i have it set to 20V (there is no 12V selcetion). So whenever i test something it will be on the 20V setting.
Heres what i've done so far...
-tested the battery to get a hang of things and it tested 14.42 while running
-Tested fuses for the lowbeams and got .00 and that was with the truck running and headlight switch to the right. Did the same test with the highs on and got over 14V
-Tested relay 46 with lows forced on and truck running. Pin 6 had a reading of -.04 Pin 2and5 had a reading of .02 Pin4 had a reading of.00
-tested the low beam plug and got .00
-tested pin A5 on the rear BCM. Now keep in mind this wire is cut and both ends go to my DRL killer. The side coming from the truck read .07 and the side going to the plug read .07. I could hear the relay click when the HL switch was turned on and off
-on a side note, i found that i blew both 194 bulbs for the front marker lights. They are now replaced and working.
I wonder if i overloaded the system somehow?
What else should i check?
Thanks,
Kevin
Heres what i've done so far...
-tested the battery to get a hang of things and it tested 14.42 while running
-Tested fuses for the lowbeams and got .00 and that was with the truck running and headlight switch to the right. Did the same test with the highs on and got over 14V
-Tested relay 46 with lows forced on and truck running. Pin 6 had a reading of -.04 Pin 2and5 had a reading of .02 Pin4 had a reading of.00
-tested the low beam plug and got .00
-tested pin A5 on the rear BCM. Now keep in mind this wire is cut and both ends go to my DRL killer. The side coming from the truck read .07 and the side going to the plug read .07. I could hear the relay click when the HL switch was turned on and off
-on a side note, i found that i blew both 194 bulbs for the front marker lights. They are now replaced and working.
I wonder if i overloaded the system somehow?
What else should i check?
Thanks,
Kevin
I hate to admit it but I finally gave up. Not having all the proper tools and knowledge has taken me to a dead end. I made an appointment for tues to get the truck looked at which is the earliest I can get in. Till then I'm just gonna drive with my high beams on and pray I dont get pulled over. I like to thank everyone who gave me advice and helped me along the way. I did learn a few things which I hope I can pass on to others down the road.
Thanks again,
Kevin
Thanks again,
Kevin
Boricua SS
Member
IAFF78 said:
in the mean time, i would still be troubleshooting up until the time of the appt. you've come this far... keep your head up man..
Thanks.
I've just run out of Ideas. I can look at the schematics but all the little symbols and lines crossing have me lost. I've tested fuses and wires and relays and I don't really know where to go from here. Hate to see what the bill for this f up will run me
I've just run out of Ideas. I can look at the schematics but all the little symbols and lines crossing have me lost. I've tested fuses and wires and relays and I don't really know where to go from here. Hate to see what the bill for this f up will run me
Blckshdw
Moderator
From what we've all gathered to this point, I think the problem will be with 1 of 2 items. Either the relay socket in the front fuse block, as previously suggested... Or the BCM has become damaged somehow, and is not pushing the signal through pin A5 (pink/white wire).
What I might try next is jumping the signal at the BCM, and see if you can trigger the headlights yourself. Get a spare piece of wire, and with the headlight switch turned on, touch one stripped end of the wire to the positive stud next to the rear fuse block, and the other stripped end to where the pink/white wire goes into your DRL killer (or exits, for that matter). In theory, if the relays/fuses in the front block are good, you should be able to trigger the low beams as if YOU were the BCM.
Edit: You probably don't need the headlight switch turned on for this
What I might try next is jumping the signal at the BCM, and see if you can trigger the headlights yourself. Get a spare piece of wire, and with the headlight switch turned on, touch one stripped end of the wire to the positive stud next to the rear fuse block, and the other stripped end to where the pink/white wire goes into your DRL killer (or exits, for that matter). In theory, if the relays/fuses in the front block are good, you should be able to trigger the low beams as if YOU were the BCM.
Edit: You probably don't need the headlight switch turned on for this
But pin 2 of the relay socket has no 12V. 
You really have no electrically-experienced friends or neighbors who need beer?
You really have no electrically-experienced friends or neighbors who need beer?
Blckshdw
Moderator
the roadie said:But pin 2 of the relay socket has no 12V.
You really have no electrically-experienced friends or neighbors who need beer?
That's right, I forgot which pin wasn't cooperating. I wonder if having the HID relay harness initially hooked up to the front fuse block stud for power could have caused this?
I did as you said. Wire was ran to positive terminal and the other end was ran to A5 before and after the relay. Both times i did this i had 12.22V to pin2&5 on the relay. Fuses 3&6 had 9.88V running to them and the headlight bulb plug had 10.22V running to it. All this was done with the headlight switch turned to the right. So is it the BCM?
Now, when i plugged in the OEM bulbs i had nothing. I wonder if I didnt store them properly? The were just placed in a plastic bin until i bought some bubble wrap to wrap them up.
Now, when i plugged in the OEM bulbs i had nothing. I wonder if I didnt store them properly? The were just placed in a plastic bin until i bought some bubble wrap to wrap them up.
Blckshdw
Moderator
IAFF78 said:
Did your 194 bulbs go out approximately the same time as your low beams? Maybe those bulbs are blown too? If you're getting voltage at the low beam sockets doing that jumper test, then that definitely points to the BCM, or at least that one wire/connection. Hopefully that just means there was a small oversight when you tested the relay socket the first time around.
I believe the 194 bulbs did blow around the same time i was having this issue. I replaced the 194's they work now. Before i did the jumper, I had no voltage going to relay 46. I even unhooked the jumper and tested 46 and had nothing register. Whats the next step/test i should do. I'm getting excited that some progress was made and hopefully i wont need to go to the mechanic.
Thanks,
Kevin
Thanks,
Kevin
Blckshdw
Moderator
I'm guessing there was a wiring hookup issue previously, that caused a surge that not only blew those fuses previously, but also your corner and low beam bulbs. How are your parking lights in the front? Those still work too?
Next thing I would try is find the wire that comes from the headlight switch that's supposed to be the signal for turning the low beams on manually. Then find that wire at the BCM, and test it for voltage, to make sure the BCM is getting the 'on' signal when the switch is turned.
Next thing I would try is find the wire that comes from the headlight switch that's supposed to be the signal for turning the low beams on manually. Then find that wire at the BCM, and test it for voltage, to make sure the BCM is getting the 'on' signal when the switch is turned.
Blckshdw said:
Parking lights work fine now since i replaced the bulbs.
I'm looking at the wiring diagram but there are multiple "HDLMP ON SIG" listed. How do i test those?