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Plow Headlight not switching on

huntingpse

Junior Member
Location
PA
I have a western uni-mount plow on a 2001 dodge ram 1500. The harness is a 9 pin plug with 2 relays. The truck head lights are HB-1. I just bought a new harness for the plow, which fixed my parking lights, but the headlights still won't switch over when I connect the plug. If I have low beams on in the truck and I connect the plugs to the plow, the headlights will work, but only when I hold the hi/low beam switch back on the steering column. Lights turn back off when I release the hi/low beam switch. Any thoughts?
 

mtk469

Member
Location
NE Indiana
I have had a similar issue a time or two. Is your 9pin truck and plowside connection good and tight? Corroded at all? Do you have your main plow plug attached as well? I can recall pulling up to one of my plows to check some light work I had done and just plugged the light plug in and not the main 2 prong plug and the lights didn't work. Plugged in the 2 prong and they worked.
Just a couple of thoughts.
 
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huntingpse

Junior Member
Location
PA
I had both of the plugs connected when I was testing headlights. Made that mistake earlier in the week.
I checked and replaced the relays. Also had a dealer check the relay connections and the the truck side wiring. He did not have time to get into the plow side wiring before they closed. Thats when I bought the replacement plow side harness. I scuffed up all connections and then greased them up before connecting.

I ran a wire with inline fuse from battery to white wire on relay to drive home. The lights work fine when wired direct. I assume it is a problem with the relays switching over, but the connections match the wiring diagrams.
 

twinman326

PlowSite.com Addict
Location
New York
The brown wire from the driver side parking lamp energize the relays attach to #86 on the relay......check at the parking lamp for any corrosion, or the wire is broken. Check the relays and wires for corrosion. If corrosion is found clean and re-attach.

Also check the grill connection for any corrosion..If corrosion is found, use battery cleaner. spray both ends of the grill connector( plow and truck harness) and use a air gun to blow it out..

Check the the black/orange wire to see if it loose at the motor relay or corrosion on the negative side of the battery, and plow frame.. Make sure all wires mention are clean and have good connections
 
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huntingpse

Junior Member
Location
PA
twinman326
I believe everything is good at the motor relay.
I know there was black corrosion on drivers side turn signal wire when I was stripping the wire on the truckside harness. I suspected the same problem, so I soldered the connection again. The question I have is: can this still be the problem if the turn signals work on the plow?

The reason I ask, is because I will need to start stripping wire in the harness to find where the corrosion stops. How can I check the relay manually to make the headlights flip on at the relay.
Thanks for your help.
 

twinman326

PlowSite.com Addict
Location
New York
Like crash was explaining check the brown wire at the motor relay. It is possible it is loose or corroded.Also look at the side marker to see if is working, and the parking light as well......

The brown wire from the marker energize the relays on pin #86......
Let us know how you are doing......
 
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huntingpse

Junior Member
Location
PA
I have power to brown wires with the lights on. Both marker lights on the plow work. I am taking the computer out with me now. To continue probing around.
 

twinman326

PlowSite.com Addict
Location
New York
Did you check the grill connector truck side??? Make sure both plow and truck are connected. Turn the head lights on, the wiggle the grill connector to see if the lights come on.

When you put the new harness on the plow, you did wire the head lights (plow lights) correctly?

Here is some wiring diagrams to help you out just in case...

9 pin truck
dodge 9pin vehicle.jpg

9 pin plow
dodge 9pin plow.jpg

Could be possible you might have a bad relay.. Check all the wires to make sure they are hook up correctly.. Also make sure they relays are clean.. Check the grill connector once again..

Make sure the black/orange wire is to the proper wires inside the light housing on the plow, and attach to the plow frame with the negative battery wire

dodge 9pin plow.jpg


dodge 9pin vehicle.jpg
 
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huntingpse

Junior Member
Location
PA
I have cleaned the grill connector twice. I hooked up the plow lights correctly and double checked all the grounds. I tried a different set of relays, and then went and bought a new set to use. I just took my truck over tonight to have tires and mounted and balanced. The mechanic is going to look at the lighting as well. Hopefully he will find something. I will let you know when I get the truck back.
 
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huntingpse

Junior Member
Location
PA
I spoke to the mechanic, and he thinks that I may have the wrong harness. Mine is a 9 pin with 2 relays as stated before. The diagram that is posted above shows 2 relays as well. There are several differant types of 9 pin harnesses depending on the truck you have. I found some other literature that suggest that I may need 4 relays. Does this make sense? Does anyone know or know where I can look to find which 9 pin harness is correct for my 2001 dodge ram w/o drl's. Snow maybe coming this weekend, and I have too much money in this to miss out. I can give my number as well if someone whats to call me.
 

Crash935

2000 Club Member
The main 9 pin harness is correct, its the cross harness and relays that are wrong. Your mechanic is right though, should have 4 relays also. Cant find my book with the part info right now to get the right part #. B&B or Arch Burn should be able to help out with the part # and/or getting you the parts you need.
 

Nasty-Z

Senior Member
Location
Poconos PA
As Crash935 said the 9 pin control harness is correct for your application ,as long as you have the dual HB1 bulbs in your dodge check to see if you have a 26009 headlight harness , there is probably a white tag somewhere on the harness with the part # . There should be 4 relays for use with this setup . 62917 is the complete wiing kit for your Dodge.

Here is the link to the instructions : http://westernplows.com/pdf/62918_011400.pdf

TOM
 
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Nasty-Z

Senior Member
Location
Poconos PA
huntingpse;974935 said:
I spoke to the mechanic, and he thinks that I may have the wrong harness. Mine is a 9 pin with 2 relays as stated before. The diagram that is posted above shows 2 relays as well. There are several differant types of 9 pin harnesses depending on the truck you have. I found some other literature that suggest that I may need 4 relays. Does this make sense? Does anyone know or know where I can look to find which 9 pin harness is correct for my 2001 dodge ram w/o drl's. Snow maybe coming this weekend, and I have too much money in this to miss out. I can give my number as well if someone whats to call me.
Where in PA are you located ? PM me if you wish

TOM
 

24v6spd

Inactive
Location
Michigan
huntingpse;974935 said:
I spoke to the mechanic, and he thinks that I may have the wrong harness. Mine is a 9 pin with 2 relays as stated before. The diagram that is posted above shows 2 relays as well. There are several differant types of 9 pin harnesses depending on the truck you have. I found some other literature that suggest that I may need 4 relays. Does this make sense? Does anyone know or know where I can look to find which 9 pin harness is correct for my 2001 dodge ram w/o drl's. Snow maybe coming this weekend, and I have too much money in this to miss out. I can give my number as well if someone whats to call me.
I have a 2001 Ram 2500 w/o drl's and I have 4 relays.
 

24v6spd

Inactive
Location
Michigan
I also remember when I switched my plow from my '98 Dodge I had to buy a harness for the 2001 that had something to do with non drls, anyhow it contains 2 fuses. Could your fuses be blown.
 

Sharpcut 1

Senior Member
Location
Roseville, MI
1. Is this a Dodge Sport?? (High and low headlights use 2 different bulbs) for a total of 4 headlight bulbs on truck??


2. Do you have the turn signal-park relay kit?? (do you have cab lights)

3; Do you have power at the greenor yellow wires at your 2 relays with the headlight switch on??

Did you try jumping your blace/orange tracer wire from your relays back to battery negative to see if your ground in your wiring harness is bad??

You should make sure you have power in at the 30 terminal on your relay with the yellow wire when your low beams are on. You should also have power at the brown wire with headlight switch on. If you have the extra relay (as a lot of the Dodge;s up to 2002 that I have worked on do) follow it back to the battery positive, and make sure the extra relay has power and ground. Let us know what you find.
 

twinman326

PlowSite.com Addict
Location
New York
huntingpse;972558 said:
If I have low beams on in the truck and I connect the plugs to the plow, the headlights will work, but only when I hold the hi/low beam switch back on the steering column. Lights turn back off when I release the hi/low beam switch. Any thoughts?
In your quote, the highlighted in red, you hold the "hi/low beam switch, they work. Maybe you have a problem with the switch it self?

Why did you buy a new harness? Did this problem just happen??

Did you have the same plow with the same hook up on this truck before you brought the harness??

Or did you just install this plow on this truck?

If so, what truck did this plow come off of?
 
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huntingpse

Junior Member
Location
PA
Nasty-Z;975090 said:
Where in PA are you located ? PM me if you wish

TOM
I have dont have enough posts to PM.
Gettysburg, PA
Local dealer looked at their book and he said it should only require 2 relays. Mechanic is still looking at it. He said he might be able to make it work...will know more tomorrow.
 
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