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RamDude01
10-09-2008, 09:00 PM
Hi everyone, been reading and gathering a lot of great info over the past couple of years and am in need of some help. I just installed the wiring in my 98 Dodge Ram 2500 for a used 2003 super duty 8' straight blade, everything seems to work except for the plow headlights. When I hit the headlight switch in the cab from truck to plow, the truck headlights go off but no plow lights coming on... switch it back to truck and the truck lights come back on. Marker lights and turn signals work just fine, goes up, down and angles just fine... anyone have any idea of what could be wrong??? The wiring, I believe, is installed correctly as it is by the book and I had my 01 Dodge sitting next to it for verification. I haven't taken the bulbs out to check them yet but I don't believe that is the problem.

I think that I also may have noticed a slight spark between the pin spring clip (that holds the pin back while mounting) and the plow frame when I was hooking it up (after hitting the smart hitch 2 button) and trying it out the other night... any thoughts on that. The wiring was used but in good condition. I did not see anything wrong with that anywhere. I haven't tried hooking up to my other plow yet to see if it is a plow side problem or a truck side problem.

Thanks in advance! http://www.plowsite.com/images/smilies/help.gif
:help:

B&B
10-09-2008, 09:49 PM
Hi everyone, been reading and gathering a lot of great info over the past couple of years and am in need of some help. I just installed the wiring in my 98 Dodge Ram 2500 for a used 2003 super duty 8' straight blade, everything seems to work except for the plow headlights. When I hit the headlight switch in the cab from truck to plow, the truck headlights go off but no plow lights coming on... switch it back to truck and the truck lights come back on. Marker lights and turn signals work just fine, goes up, down and angles just fine... anyone have any idea of what could be wrong??? The wiring, I believe, is installed correctly as it is by the book and I had my 01 Dodge sitting next to it for verification. I haven't taken the bulbs out to check them yet but I don't believe that is the problem.Are you positive you have the correct head light adapters (if your application uses them)?

I think that I also may have noticed a slight spark between the pin spring clip (that holds the pin back while mounting) and the plow frame when I was hooking it up (after hitting the smart hitch 2 button) and trying it out the other night... any thoughts on that. The wiring was used but in good condition. I did not see anything wrong with that anywhere. I haven't tried hooking up to my other plow yet to see if it is a plow side problem or a truck side problem.
The spark you saw is due to a poor ground. The plow is attempting to dround through the truck mount as it get near. This is due to a poor ground connection either at the pump motor itself, the truck side ground connection, or at the power connector plug. Start with cleaning the ground cable connections starting at the connecting plug and move your way to the plow. Pull the pump cover off and clean the ground cable where it's attached to the tower.

nobletousha13
10-09-2008, 10:19 PM
check the inline fuse going to the battery. with out that power going to the relays there will be no plow lights. if the fuse is not blown make sure the fuse holder is has not sepereated, meaning the rubber will pull the connections apart just enough to not make a good connection. if thats the problem just smash them back together.

B&B
10-09-2008, 10:23 PM
check the inline fuse going to the battery. with out that power going to the relays there will be no plow lights. if the fuse is not blown make sure the fuse holder is has not sepereated, meaning the rubber will pull the connections apart just enough to not make a good connection. if thats the problem just smash them back together.Never hurts to check fuses of course, but if that were the case the truck lights wouldn't go out when the switch was flipped either, which they do, so that means the relays are getting power and at least one of them is being tripped.

RamDude01
10-10-2008, 11:21 AM
Thanks for the input. The truck side grounds should be good. I cleaned all the wiring harness connections before installing on the truck side so I believe those should be good. It didn't require any headlight adapters so those are connected properly. I'll check the fuses also... I am planning on looking more at it tomorrow as the weather is supposed to be better. I'll let you know if I find anything.

RamDude01
10-10-2008, 11:36 AM
Another question... there are four relays, can someone tell me what they are for and which one does what?

Thanks!

B&B
10-10-2008, 05:25 PM
So this is a used harness? What year/model truck was it removed from? What head light style does your '98 Dodge have? HB1's (9004 bulb) correct?

You are aware that the vehicle option plug in the plow harness needs flipped 180 degrees for the '94-'02 Dodges with the single HB1's right?

RamDude01
10-10-2008, 09:55 PM
Thanks B&B!

Yup, the wiring harness was used. I was told that it came off of a Dodge. My 98 has the single headlight bulb so I take it is the HB1. The harness had the correct headlight adapters as they were, just plug and play.

No, I wasn't aware of the vehicle option plug needing to be flipped. Where might I find that and what exactly would I need to do?

Thanks again!

B&B
10-10-2008, 10:10 PM
Thanks B&B!

No, I wasn't aware of the vehicle option plug needing to be flipped. Where might I find that and what exactly would I need to do?

Thanks again!The option connector will be tucked in the harness about a foot or two from the relay pack. Will be a black rubber two wire inline connector. Simply disconnect it, flip it 180 deg and plug it back together.

Make sure you check the head light fuses afterward as it usually pops the fuses when connected incorrectly.

RamDude01
10-10-2008, 11:05 PM
Thanks again B&B! I'll take a look at it when I get home tonight. Are the headlight fuses you are talking about for the plow headlights or the truck headlights? If they are for the plow lights, where would they be? Sorry to ask so many questions... just not too familiar with the wiring stuff. I take it it must be for the plow lights as the truck lights are still working... thanks again!

B&B
10-10-2008, 11:10 PM
The light fuses I was referring to are for the truck head lights...so if they're working fine I'd say you didn't pop any. :drinkup:

RamDude01
10-10-2008, 11:20 PM
Thanks, I'll try to switch that connector as see what happens... if that doesn't do the trick do you have any other thoughts of where to look?

B&B
10-10-2008, 11:24 PM
if that doesn't do the trick do you have any other thoughts of where to look?Only other likey cause would be a bad relay or poor connection in the relay pack causing one of the relays not to switch when you flip the switch.

RamDude01
10-10-2008, 11:26 PM
Thanks B&B for all the help so far. I'll check things out tomorrow and let you know what happens. Have a good one!

RamDude01
10-11-2008, 10:14 PM
Hi B&B, thanks for all the help so far... well, today I checked out the plow. I pulled up to the plow to hook it up and it seemed to act kind of intermittent with the power while hitting the smart hitch 2 button. So I took the cover off on the plow and the ground wire on the motor was a little corroded to I took that off and cleaned it and put it back on. I think that helped with the ground problem...

I was switching the headlight switch from truck to plow a few times and the low beams finally came on. They switched on and off and seemed to work okay for awhile. High beams would not work on the plow, only low beams. I started looking at the relays, checked the fuse - was good, and started exchanging the relays one by one putting in a relay that I know was good from my other truck. First one, still the same, second one - no headlights, third and fourth - headlights on plow no longer working... so now I am back to no headlights on the plow. I hooked up my 01 truck and the plow lights and everything worked fine. I hooked the 98 truck to the other plow and the same thing, no headlights. So I believe the problem is with the truck side wiring. As far as I can tell, everything is hooked up by the book and I also had my other dodge as the 'template' for where everything went...

As to the option connector was plugged in the same as my 01, red to white and white to red, so I believe that is the way is should be.

The other thing that now seems to be happening is when I push the smart hitch 2 button to hitch it up, the relay clicks and there is nothing, just the clicking from the relay. I can manually push the tower up and engage and then when I go to unhitch it, the smart hitch 2 seems to work okay.

Thanks again for all the advice and help!!!

aeronutt
10-11-2008, 10:44 PM
Rather than blindly switching the option plug and blowing fuses, why not look at the schematic and know for certain that you are setting it correctly? You can pull the schematic from the Boss website. I haven't read the Dodge directions, but Chevy had different setups for different year models. Watch out for that...

EDIT: I just looked up the schematic for Dodges. 2003 & newer with 4 headlights uses standard connection, older with 2 headlights uses reverse. Your connection is correct with red to white & white to red. I'd bet a Big Mac your problem is a bad ground from the relays.

More EDITS: If you read my original reply, it was wrong. Here's better info...
For your other questions, there are 4 relays because there are 4 circuits. One switches on the whole system when the key is turned on. The other 3 activate simultaneously to switch Low, High, and Ground from truck to plow when you flip the switch. I just got done reading the schematic and it breaks my truck's original design by crossing both low beams into a single circuit and both high beams into a single circuit. The truck was desiged so that Each headlight is individually fused (4 fuses total) in order to give you the maximum possible lighting options when one fuse pops. Now it has 2 10-amp fuses in parallel that will both pop if something shorts out. I'm not really liking that...

The Boss wiring harness taps in after the truck fuses, so both the truck's lights and the plow's lights are protected by the truck's fuses. If you blow a headlight fuse it will affect both the truck and the plow. If you have a relay go bad, the relay in question will not switch between truck and plow when the other 3 do. If the bad relay is the one that switches ground, nothing works when you flip the switch. If it's the high or low beam circuit, only the other one will switch. You didn't ask this, but just as fair warning: don't bypass the relay and run both truck and plow lights at the same time because the lights draw about 4-5 amps each. 16-20 amps of lights on two 10 amp fuses = :realmad: when the fuse waits until you are pushing snow to finally give up.

Did you try taking ALL the relays out of one truck and puting them in the other truck?

The inline fuse near the battery on the boss wires only protects the relay coils that are activated by the truck/plow dashboard switch and the joystick. If that fuse blows, the truck lights should work normally and the plow won't move at all

RamDude01
10-11-2008, 11:12 PM
Aeronutt, thanks for the info. I've looked at the schematic as you suggested and the option plug is hooked up correctly. Everything seems to be in order as far as I can tell. The truck lights work normally, low beams and high beams, just nothing on the plow. Like I said, for a short while I actually had low beams working... now again, nothing on either plow.

Thanks for the clarification on what the relays are for and the suggestion to look at the schematic, that was very useful. Have any thoughts on what the problem could be other than what I've tried?

Have any thoughts why the relays seem to click, or what else would be clicking, when I hit the smart hitch button to hook it up and why that wouldn't be working to hook it up but seems to work fine to unhook it? This thing is baffling me....

sabres07
10-11-2008, 11:27 PM
Ramdude, I think we have similar problems going on...concurrent threads. I, too, had the lights working yesterday on the plow, but today...nothing. My relays sound like they are clicking, but trucks headlites stay on. In fact, at one point I had the truck and plow lights working at the same time, and when i hit high beams, the truck fuses blew....too much draw. I think I have it isolated to corrosion on the trigger relay or possibly the red/black wire under dash hooked to improper ignition power source. I am still hoping BB can answer that for me....:redbounce

aeronutt
10-11-2008, 11:59 PM
It seems like no matter what I'm working on, electrical problems always end up being something far too simple that gets overlooked. Proper grounding and clean contacts end up fixing glitchy gremlins more often than failed components. It took me a few tries to get my previous reply accurate so go back up and re-read it too. I was flat-out wrong when I posted it initially...:dizzy:

Try pulling all the wires off (especially ground wires under the hood) and buffing the terminals with 400 grit sandpaper to absolutely remove any possible doubt about the quality of the connections. Use plenty of dielectric grease when reassembling to prevent corrosion problems later. If that doesn't get you going, swap ALL the relays from one truck to the other. If that doesn't change anything then about the only thing left is tracing out the wires with a test light or multimeter. It shouldn't come to that though...

grassplus
10-12-2008, 01:15 AM
Have any thoughts why the relays seem to click, or what else would be clicking, when I hit the smart hitch button to hook it up and why that wouldn't be working to hook it up but seems to work fine to unhook it? This thing is baffling me....

possibly corroded power and ground cables going between the truck and plow. where they connect together gets worn. if you look inside the connection there is a split on the male contacts. put a small screwdriver in there and split them apart so they make good contact. My V hesitated while hooking up last year and that fixed the problem. (2001 dodge)

B&B
10-12-2008, 01:38 AM
I, too, had the lights working yesterday on the plow, but today...nothing. My relays sound like they are clicking, but trucks headlights stay on. In fact, at one point I had the truck and plow lights working at the same time, and when i hit high beams, the truck fuses blew....too much draw. I think I have it isolated to corrosion on the trigger relay or possibly the red/black wire under dash hooked to improper ignition power source. I am still hoping BB can answer that for me....:redbounceI agree it sounds like a corrosion problem or a short somewhere as it should NEVER have both the truck and plow lights on at the same time. Even if you don't have the plow connected the truck lights should go out when you flip the light switch to the plow position. I'd be pulling all the relays and checking the sockets for corrosion, as well as swapping in some known good relays.

Have you verified that ALL THREE of the relays that control the lights are clicking when you flip the head light switch? You can feel them click if you place a finger on each one as a helper flips the switch. I do suspect that at least one or more is working...but they all have to work to work correctly.


BTW, just for verification your option connector is orientated correctly if the color codes are opposite of one another...and you now also mentioned that this harness was off an '01 Dodge so it would have been the same orientation.

RamDude01
10-12-2008, 02:00 AM
Thanks everyone for the input.

Aeronutt, Before I put the wiring in, I cleaned up all the connection ends thoroughly and greased them up so I don't think that is the problem. Is there another ground wire on the plow under the 'hood' other than the black one on the pump? And no, I didn't get the chance to swap out all the relays from the other truck as the son-in-law took it home, but am planning on hopefully trying that tomorrow.

Talk about simple wiring problems... I picked up this truck last spring for a second plow truck. Got a good deal on it with a new engine with less than 35k on it and a rebuilt tranny. Since I got it the headlights and interior lights would flicker something awuful... Everyone that I talked to said it had to be a bad ground so I replaced almost all of the ground wires and regrounded everything else that I could find, nothing helped... was getting a little frustrated. And then shortly after getting it the alternator went out, replaced it and then the battery started not charging. Took it back to the store where I got the alternator from and they tested it and said it was bad so replaced with another one, still wouldn't charge the battery. I was about to give up and take it to the dealer and take it in the shorts when I stopped down at a buddies house to give it one final go over... just for the hell of it, I took off the wire from the fuse block under the hood going to the positive battery connection and filed it down, cleaned everything up and put it back on... low and behold all the problems went away. Has worked perfectly since and all it was was that one connection being dirty.

Grassplus, I'll also check the power hookup between the plow and the truck to make sure that they are making a good connection.

sabres07 - I did notice a little bit of corrosion on a few of the relay terminals when I was pulling them out. I cleaned them up and then nothing... so far I haven't had any problem with both being on at the same time, when I flip the switch the truck lights go off, but no plow lights. The switch seems to be doing what it is supposed to do as the truck lights turn off and on...

Thanks again for all the help and input, I greatly appreciate it. I'll keep working on it and keep you posted.

RamDude01
10-12-2008, 04:01 PM
Well, today I replaced all the relays with new ones. So far the low beams are working again. Still no high beams. I pried apart the male power connections slightly and it seemed to hitch up and unhitch okay. So that's good news. I also replaced the connections to the battery for the relay power and ground. Any idea why the high beams won't work???

Thanks!

aeronutt
10-12-2008, 05:52 PM
It's probably a "DUH", but are you sure the high beam bulbs are good? I spent 5 hours trying to find an electrical gremlin once because I refused to believe that BOTH headlights burned out at the same time... It happens...

If that's not the problem, I believe it's time to pull out the multimeter and test for power at the plugs going to the plow. Check the schematic for which wire carries the high beam juice and see if it energizes when you flip the switch. Are the truck's headlights turning on and off appropriately when you flip the switch?

RamDude01
10-12-2008, 06:02 PM
Hey aeronutt, I haven't tried changing the bulbs yet... still on my list, was thinking of that though. The truck lights are turning on and off normally, on truck - both highs and lows, on plow - so far only lows...

I was on my way to the store to pick up bulbs to try that. The ones that are in there look to be okay but am planning on changing them out anyway.

B&B
10-12-2008, 06:49 PM
Have you verified that ALL THREE of the relays that control the lights are clicking when the toggle is flipped to the plow light position?

When you had the plow hitched to your other truck you didn't try the plow hi beams? That would have told you right there whether the hi beams on the plow are good or not.

RamDude01
10-12-2008, 07:58 PM
Hi B&B, yes, when I had the other truck hooked up all the lights worked. I haven't verified the clicking of the relays yet as I have been the only one home most of the day. I did take my test light out and if I am reading the '13 pin functions' off the boss site correctly, the low beams should be pin 8 and highs should be pin 7. I have power on the low beam pin and no power on the high beam pin.

RamDude01
10-12-2008, 08:04 PM
B&B, all relays click when the switch is flipped.

aeronutt
10-12-2008, 09:25 PM
OK, I know this is going to sound a little weird, but try switching the relays around. It's possible that they are clicking, but not making contact internally. You said you bought 4 new relays? :confused: I'm "thinking out loud" here... No power at pin 7 (yes, that's the highbeam pin) guarantees that the lights won't light. Need to track back from there. The wire goes directly from the relay to the plug. We know you get power into the relay because the truck lights work. We know the relay disconnects the power from the truck lights. We know that when it disconnects the truck lights, it is SUPPOSED to connect the power to the plow lights. What we DON'T know is if the relay is actually sending power down the plow wire when it disconnects the truck wire. If you remove relay 1 and try it again, everything should work as before except that the high beams won't work at all on either the truck or the plow. If you accidentally remove relay 4 thinking that it's 1, the whole plow system won't work. Once you are sure you got 1 not 4, switch relays 1 & 3. If you have a bad relay the problem will migrate to the low beams. If the problem stays on the high beams then the only thing left is a broken wire in the harness between the relay and pin 7 in the 13-pin plug or a relay signal wire. You can confirm this by removing relay 1 and jumpering a wire directly from spade 30 (goes hot when highbeams are on) to 87 (far opposite side, rotated 90 degrees from pin 30) and turn on the high beams. The plow high beams should light if the wire is good. Change the jumper to go between 30 and 87a (in the middle) and the truck high beams should light. One other test you can do while you've got the relay out is to test for 12v between pins 88 and 85. 88 should go hot when the dash switch is on "plow" and and go cold when the switch is on "truck". Pin 85 is the coil ground for the relay.

I got all my information from page 18 of THIS (http://service.bossplow.com/Documents/stb03278.pdf)document. Double check that I guessed correctly for which instruction sheet to look at.

Assuming I didn't confuse you too much, do all this and report back.

RamDude01
10-14-2008, 11:16 AM
Will look at it again later in the week. Kinda busy these days. I'll let you know what I find. Thanks for the help!