Electrical issue (strange!)

[OB99W]

This is a OBDII Can-bus system. Meaning it uses a multiplexed communications bus under the hood (I think or uses it to some degree). Maybe some place in here lies the answer, but, considering i used to wire test cells for large equipment (bomb racks sonar systems mine sweepers)), its possible something very very very wierd is happening along those lines. Professionally speaking, i dont think there is enough RF energy from any of these components to cause this.

I believe the Subaru BIU handles things such as lighting, as well as the less mundane keyless entry, immobilization, CAN-bus, etc. As has been mentioned, connecting a random piece of wire to the battery post or alternator output could certainly act as an antenna, and there can be plenty of electrical noise generated by the starter and/or alternator (or something we're not aware of) for it to radiate. Ideally, the battery has very low internal DC resistance, but AC-wise that's less the case and therefore signals need to be protected via shielding or decoupling (inductive/capacitive filtering).

 

I assume BrightLights isn't yanking our chains, so maybe ''Twilight Zone'' really is the explanation.

[89Ru]

For a quick shield, use aluminum foil wrapped around the hot wire insulation, tie the foil to the (-) battery or some clean connection to body with some alligator clips. If this works, a more robust shield can be made using heavy gauge ground braid, either the wrap method or thread the hot lead through the birdcaged center of the braid. Maybe you have an electrical supply store in your area?

[OB99W]

How about contacting SOA and seeing if your hunch is correct? Or any friendly anti-theft installer?

Or perhaps talk to these guys: http://www.the12volt.com/installbay/. The ''Car Security and Convenience'' forum there might be an appropriate one.

[EVOthis]

I'm just throwing this out there...You are aware when you disconnect the battery or clear the codes in these newer Subarus. the first time you attempt to start the car it wont start...its a feature of the system...however on the second or third attempt it should turn over and start. I'm assuming you've tried to start the car multiple times with the wire attached?

[BrightLights]

I assume BrightLights isn't yanking our chains....

 

I assure you I am not. I went through a lot to mount the lights and to try to troubleshoot the install. As of right now, I have beautiful Cibie lights fully mounted and wired (except for the *one* wire), and they are for the time being purely ornamental. You can all imagine, I am sure, how frustrating this is. I'll take a picture and post it tomorrow or Wednesday.

[BrightLights]

I'm just throwing this out there...You are aware when you disconnect the battery or clear the codes in these newer Subarus. the first time you attempt to start the car it wont start...its a feature of the system...however on the second or third attempt it should turn over and start. I'm assuming you've tried to start the car multiple times with the wire attached?

 

Early on I tried to start the car multiple times. I admit that lately I have just been trying once. By the way, the car always turns over strongly, even on the first try after re-connecting the battery; it simply won't catch at all.

 

I think the next thing to try might be to attach the wire to the battery "+" terminal and the relay and then, instead of trying to start the car, turn the key to the accessory position, let the car go through its "full sweep" sequence, *then* try to start the car. This is just a hunch on my part, but maybe if the car is switched to the accessory with a proper key (with the embedded chip), the car will sense the wire, however it does that, and decide that it's okay.

 

If that doesn't work, I'll try the other things suggested. This may not happen until later in the week due to commitments/weather, but I am eager to get ot the bottom of this and grateful for all the help from this forum.

[BrightLights]

For a quick shield, use aluminum foil wrapped around the hot wire insulation, tie the foil to the (-) battery or some clean connection to body with some alligator clips. If this works, a more robust shield can be made using heavy gauge ground braid, either the wrap method or thread the hot lead through the birdcaged center of the braid. Maybe you have an electrical supply store in your area?

 

Thanks very much for this excellent suggestion. Yes, there is an electrical supply store about 15 miles away in Montpelier. I just didn't know what to ask for, but now I do. Thanks again.

[BrightLights]

Any amount of tinkering may not defeat the anti-theft, if it is really sensitive. How about contacting SOA and seeing if your hunch is correct? Or any friendly anti-theft installer? If you are right, then the anti-theft should have a mode where it can store the new signature, and off you go.

 

I called SOA and they politely but firmly declined to help. Same with the service manager at the local Subaru agency. I bet there is a reprogrammable parameter that would take care of the issue, but SOA and my dealership aren't talking.

 

Your suggestion that I consult an anti-theft installer and OB99W's suggestion that I visit http://www.the12volt.com/installbay/ are good ones.

[Cougar]

I like your thought about the key OB99W. There may be RFI coming from the starter motor and the lead is causing the noise to get to places it shouldn't and is causing trouble.

[Fairtax4me]

With regard to trying shielded wire, where does one go shopping for shielded wire of an appropriate guage (12-14 preferable)? I'm just familiar with house wiring, audio sound systems, and old-school car wiring, none of which use shielded wire (except for low voltage mic and line cables; speaker cables are unshielded).

I've bought it at Radio shack before, but that was long ago. I would imagine an electronics specialty store would have some. Or you could just make some with aluminum foil as was previously suggested.

[BrightLights]

Progress is being made. I have answered the question I posted, but that has led to another, which I hope you can help me with (it's far less mysterious).

 

First things first. The solution to makeing the car start with a new wire attached to the battery "+" terminal turned out ot be very simple (I went to town yesterday and bought heavy duty aluminum foil and large alligator clips, but this turned out to be unnecessary). The car goes through a little self-test routine when you start it. All of the guages go through their full sweep and all the warning lights come on, then go out. When you start the car normally, you shoot right past the "accessory" position on the ignition switch to the start position. *After* the car turns over and starts, it goes through its self-test routine. I was never getting to this point because the car would not start with the wire connected to the battery.

 

The solution was to connect the wire from the battery to the relay, then turn the key only as far as the "accessory" position. The car went through its self-test routine with the key in that position. I turned the key to "off", then started the car normally. It starts normally every time now with the wire from the battery to the relay connected, so that problem is solved.

 

But I have encountered a problem wiring up the trigger circuit. The driving lights must, by law, be wired to come on and off with the car's high beams. I *thought* I had the correct wire tapped. The high beams each have a push on connector with two wires, one white and one green. I pulled the connector, switched on the brights, and used a circuit tester to determine that there was voltage between the green wire and ground and no voltage between the white wire and ground. So I tapped the green wire. Logical enough, but apparently wrong.

 

After solving the no-start problem, I discovered that the driving lights came on with both the low and high beams (though not with the headlights turned off). So I investigated further and found that there is voltage between the green wire and ground with *either* the high beams or low beams on, and voltage between the white wire and ground *only* with the low beams and not the high beams.

 

Can anybody help me determine what wire I should tap as the trigger voltage for my relay so that the driving lights come on with the high beams but not the low beams?

 

Many thanks, again, for any help.

 

Here is a picture of the mounted lights:

[Cougar]

Tie relay pin 86 to the middle power lead going to the head lights. Tie pin 85 along with your added switch in series to the switched ground side of the high beams.

Edited August 31, 2009 by Cougar

[BrightLights]

Since the head lights are switched on by making a ground connection you need to connect your relay coil (pin 86) to the middle power lead going to the head lights. That will supply power to the relay coil and when the relay switch is turned on it will ground the connection to the other side of the coil, turning on the relay.

 

Hi, Cougar, and thanks for your reply. I'm not sure I follow you, though. The high beam sockets have only two wires, one (green) has voltage to ground when either the high beams or low beams are on, and one (white) has voltage to ground only when the low beams are on. I cannot locate any "middle power lead" going to the high beams. As I mentioned, for the trigger circuit for the relay I need a trigger voltage that is only present when the high beams are on.

 

Cany you clarify? Many thanks again.

[Cougar]

I edited my previous post. In response to your last one, try this. Tie pin 86 to the power side of the high beam light, Then tie pin 85, along with the added switch in series to ground.

Edited August 31, 2009 by Cougar

[Fairtax4me]

You can run a line from the dimmer switch under the dash, or the high beam relay to a normally closed relay. When the highs are switched on the relay cuts power to the relay you have wired up for the lights.

[89Ru]

I see that you need the logical 'inverse' of the white wire (voltage at high beams and no voltage at low beams). Maybe you can still use that pesky white wire. If you can find a 30 amp normally closed relay (swapped from the normally open version you have now) you can use the white wire to trigger it. Keep wiring as is. The Bosch relay doesn't have a set of normally closed contacts built in does it? Maybe another trip to Montpelier before the leaf peepers start swarming

[BrightLights]

I edited my previous post. In response to your last one, try this. Tie pin 86 to the power side of the high beam light, Then tie pin 85, along with the added switch in series to ground.

 

Hi, Cougar. Maybe I'm just slow, and I certainly am unexperienced with the new breed of car electronics, but I am having trouble following your advice as applied to my car. My intent was *always* to tie pin # 86 on the relay to the power side of the high beam. That way, if the high beam goes out I still have the driving lights.

 

The problem I am wrestling with is that I cannot identify the power side of the high beam. The high beams and low beams are separate on my car. The high beam has a push-on connector with just two wires. With the plug pulled from the high-beam bulb, and testing for voltage between the terminals in the push-on connector and ground, I get thew following results:

 

green wire: voltage to ground when headlights turned on and low *or* high beams selected;

 

white wire: voltage to ground when headlights turned on *only* when low beams selected.

 

(The bulb seems to be well insulated and does not appear to ground through the headlight housing, but I can't be sure of this.)

 

This is unlike anything I have previously experienced, and, given these results, I am unable to identify any power side for the high beam. The green wire has power whether the high beams or low beams are selected, even though it is connected to the high beam bulb, and the white wire has power only when the low beams are selected even though, again, it is connected to the high beam bulb.

 

Any thoughts? Or am I missing something I shouldn't be?

[BrightLights]

I see that you need the logical 'inverse' of the white wire (voltage at high beams and no voltage at low beams). Maybe you can still use that pesky white wire. If you can find a 30 amp normally closed relay (swapped from the normally open version you have now) you can use the white wire to trigger it. Keep wiring as is. The Bosch relay doesn't have a set of normally closed contacts built in does it? Maybe another trip to Montpelier before the leaf peepers start swarming

 

No, the Bosch relay operates only as normally open. I am hesitant to try your approach since I do not know the function of the white wire. It seems odd, but I am wondering if that is how the voltage fed to the high beams gets to ground: The green wire has voltage whether the high beams or low beams are selected and the white wire has voltage only when the low beams are selected. Is it possible that selecting the high beams permits current to flow from the green wire through the high beam bulb and then to ground through the white wire?

[Fairtax4me]

So the green wire has voltage at all times when the switch is on. Did you check the white wire for continuity to ground when the highs are on?

 

I'm thinking its something like this.

They've got this drawn up with marker lights but it can work with any bulbs just the same. The purpose of this is to make the side marker alternate blinking with the front turn signal bulb. Normally the side marker is just on solid. By cutting the ground of the side marker and splicing that into the signal wire of the front marker/turn signal bulb, the side marker light grounds THROUGH the bright filament of the signal bulb. For some reason (I'm not well enough educated about electricity to explain how this works) the side marker will light and the bright signal bulb will not. But once the turn signal is turned on, the signal bulb lights, which I guess cuts the ground path of the side marker bulb, which then turns off. And the bulbs alternate blinking.

Maybe there is some circuitry similar to this with the high and low beam bulbs in your car.

[89Ru]

Is it possible that selecting the high beams permits current to flow from the green wire through the high beam bulb and then to ground through the white wire?

 

Yes, white wire is the return to ground. The circuit puts voltage on the white wire to turn off the high beam bulb (i.e. both sides of the high beam bulb are at voltage, so no current flows). A connection to ground via the white wire is made when only the low beams are on.

 

Not sure if both high and low bulbs are on in high beam mode. Pull the low beam connector to find out and make the same measurements as with the high beam connector. If the low bulb is off in high beam mode, you could use its return wire to ground to trigger your normally open relay.

[Cougar]

Sorry for the confusion Brightlights, I will try to be more specific. You stated that the green wire has power running to it when either the low or high beams are selected. This is the wire that should tie to the high side of the relay coil connection and the other end of the coil ties directly to ground through the added switch.

 

Now if you want the new lights to be able to be turned on only when the bright lights are on, and not the low beams, we need to make the ground connection a different way. You will need to tie the high (power) side of the coil to the green power lead but then tie the low (ground side) to the white wire of the high beam light. The ground for that light will only be connected to ground when the highs are turned on. You are just adding a parallel circuit for the relay coil across the high beam light.

 

EDIT:

I see what was confusing you about the white wire having voltage on it when the low beams are ON. The voltage you saw on the wire was there because that wire was not tied to ground when the low beams are on. That wire was floating, not tied to anything (except the open switch connection) on that end. When that happens the voltage going the light passes through the filament and to the end of the wire. There is voltage there but the current has to pass through the load in order to get to the end of the floating wire connection. If you touched that lead to ground it would turn on the light and the voltage would drop to zero since the wire is tied to ground. This is what happens to all circuits when current isn't flowing and the circuit is open. When the circuit is completed and current flows then you won't have to be concerned about floating voltages.

Edited September 1, 2009 by Cougar

[89Ru]

The voltage you saw on the wire was there because that wire was not tied to ground when the low beams are on. That wire was floating, not tied to anything (except the open switch connection) on that end. When that happens the voltage going the light passes through the filament and to the end of the wire.

 

This is all quite true, however, unless I'm mistaken, the measurements were made open circuit (looking into the two-wire mating connector for the high beam light so the filament was out of the circuit).

 

Regardless, I believe Cougar has the solution, using both high beam green and white wires across the relay trigger contacts to energize the coil (of your bosch normally open relay) should result in the driving lights being on with the high beams.

[Fairtax4me]

Which would work fine, except that's not the way it's allowed to work. Legally the driving lights have to turn OFF when the high beams are turned ON.

[BrightLights]

This is all quite true, however, unless I'm mistaken, the measurements were made open circuit (looking into the two-wire mating connector for the high beam light so the filament was out of the circuit).

 

Regardless, I believe Cougar has the solution, using both high beam green and white wires across the relay trigger contacts to energize the coil (of your bosch normally open relay) should result in the driving lights being on with the high beams.

 

You are not mistaken. I tested for the presence of voltage to ground with the connector physically removed from the high beam, so that (1) the bulb/filament was completely out of the circuit, and thus (2) there was nothing connecting the green wire electrically to the white wire.

 

I see a potential problem with Cougar's solution, but maybe it's no problem at all. The idea with Cougar's solution would be that the green wire supplies current to the trigger circuit (connecting it, say, to pin #86 of the relay) and then tying pin #85 to the white wire would permit a path to ground when the high beams are selected. There would then be a complete circuit for the trigger current, the relay would close, and the driving lights would come on.

 

The potential problem I see is that when the high beams are selected, current will be flowing from the green wire, through the filament, and then to ground through the white wire. Will this current flowing through the white wire when the high beams are on interfere with the trigger circuit's path to ground through the same white wire?

 

Thanks a million for all your help so far. Please tell me if I'm off base here. If Cougar's solution won't work, I have a more involved solution involving a second relay that I think would work, but simpler is much better.

[BrightLights]

Which would work fine, except that's not the way it's allowed to work. Legally the driving lights have to turn OFF when the high beams are turned ON.

 

Hi, Fairtax4me. In Vermont it's exactly the opposite. By law, driving lights have to be wired to come on and off with the high beams. You can have no more than two. And they have to be mounted lower than the car's headlights or, if not, be covered when on a public road. It's all right there in the motor vehicle inspection manual, available for download at:

http://www.aot.state.vt.us/dmv/INSPECTION/INSPECTION.htm

 

See page "Car 5.10":

 

6. Driving and Fog Lamps. Two (2) driving lamps and two (2) fog lamps are permitted on a vehicle provided they are wired to prevent lighting more than two (2) at the same time.

 

a. Fog to assist low beam only.

 

b. Driving to assist high beam only.

 

Any driving or fog lights mounted higher than the headlights must be covered when vehicle is being operated on the highway.