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harness compatibility '00 chev-04 sierra

Discussion in 'Western Plows Discussion' started by oakridgedriver, Nov 23, 2012.

  1. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    I am new to the site and it looks great, very useful info generated.

    I have checked out the site, however could not find an answer to my question, which is;

    Can I simply switch over the wiring/harness from a 2000 Chev to my 2004 sierra, for a straight blade poly? I have begun the process of installing the wiring, and it appears it should work, or at least connect in all the right spots. I did however get the schematics from western and the two years appear to be a bit different. Would I be fine with the relays coupled as they were from the 00? Or do I have to make changes?

    I am in the Eastern Toronto area, anyone know of a cheap outlet to get relays?

    Any other thoughts regarding the change over would be most appreciated.
     
  2. mishnick

    mishnick 2000 Club Member
    Messages: 2,243

    Being new to the site you won't know that we need more information to help you... First you need to tell us what generation of plow you have. You mentioned its a straight blade poly but is it a uni or ultra-mount? How many plugs do you have at your grill, two or three? Obviously you have relays, since you need to buy some. I am expecting you to say it's a uni-mount with two plugs. One plug has two large pings for the motor and the other probably has 12 smaller pins right?

    Assuming this to be true I won't be much help to you because I have never built a new plow with relays, my Western days began well isolation modules took over. I have fixed many but never had to choose the harnesses. I will tell you what I know and hope it helps. Surely one of the old timers will pipe up and steer you right if I get it wrong.

    What I would be looking for is the number of headlights and their type. If both have four headlights or both have two then I would say things should just switch over. But if the 2000 had two and the 2004 has four then I would be looking for a new headlight harness designed for the new truck.

    There are some other issues with DRLs (daytime running lights) which involve diodes. Can't elaborate but can just give you the heads up.

    As far as relays go, these are very common, used in lots of cars and trucks. Take a sample to Napa or Auto Pro and they will be able to fix you up. You could even go to the local scrap yard and just look through old cars. Many late model vehicles will have this same 5 pin single pole double throw relay in their fuse boxes. They are used for lights, fuel pumps, wirpers etc.

    Hope that helps, but hold on a while and I am sure someone with more relay / uni experience will help you out. Just post those details about the type of plow, plugs etc.
     
  3. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    Thanks for the reply.

    The plow is a unimount, and has the 2 connector plugs as you said.
    Looking on the wiring schematics for both 99-02, and the 03 onwards, shows basically the same number of plug ins/connections for both, and I did see the DRL designations there too. The difference I do see so far is that the wiring colours are different for the different years so it would be harder to trace all the wires back to match up.
    There are two sets of headlight male/female plugs for each side and the turn signal/parking lights tapping directions appear to be the same.
     
  4. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    Forgot to mention the number of lights....
    the '04 sierra it is going on, has 4,
    I am not sure how many the other truck ( '00 chev) had, plow was removed from truck before I bought it, that being said however, when I was on the western site, it appears they (chev/sierra) use the same harness.
     
  5. basher

    basher PlowSite Fanatic
    from 19707
    Messages: 8,992

  6. nealybird

    nealybird Senior Member
    Messages: 717

    yea, the 99-02 chevy and the 03-06 chevy wiring both have the same type of plugs and both used 6 relays, but Western had to go with a 12 pin main harness and different h/l harness on the 03-06.
    however that relay wiring is no longer available from Western. neither is the 99-02 type. You should still be able to find some somewhere hopefully.
    But does anyone know what the result would be if he went ahead and used the 99-02 wiring? I'd like to know, if anybody has tried it.
     
  7. mishnick

    mishnick 2000 Club Member
    Messages: 2,243

    You should be able to look at the harness and see how many plugs are at each headlight section. If it is for a quad headlight system there will be two female plugs (for the original vehicle to headlamp plugs) and two male ends, on each side, for the western harness to plug the redirected signal to the truck lights.

    As far as the common ground / common positive, that is just a matter of some creative adaptation in the way you hook up to the relays. If you are strong with electrical and have the original schematic I would give it a shot.

    However, that being said.... if this project was brought into my shop I know they would try to sell an upgrade to isolation module. The upgrade is more money but you can give a "for sure" price on the job. X $ for the cables and iso module and X $ for the labor. With what we are encouraging you to do it will take an unknown amount of time. At $100 / hour if it takes ten hours of try experimentation and reverse engineering you would not be impressed. At least with an upgrade you will have all new wires and controls in the end. This is a tough call. All depends on your technical skill, or.... how good a friend are you with the guy who is good at this??? Wish I lived closer, this would be an awesome challenge if only to be able to say "it can be done and this is how."
     
  8. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    My harness has the 12 pin connection, although I can't say if all pins are utilized though.

    I did read through page 11 as Basher provided (thanks by the way). Does the info on page 11 imply that to utilize the harness I have I determine which load switching the lights carry and turn the connection plugs over to match and the harness works in that configuration without altering the relays?
    I did read from another post that someone added LED bulbs to the plow assembly and direct wired, on the premise that the LED's did not add much load so did not need to be isolated or switched. I checked around town here in eastern GTA (Toronto) and have had no luck in finding those bulbs.

    Wondering (if the plow harness is not requiring any connections from the light harness) if so, I might be better off to wire up seperate connections to/from the light system on both the plow and truck and just make the extra effort to plug in/out with the connections I would wire in for all the lights?

    Thanks for the help.
     
  9. mishnick

    mishnick 2000 Club Member
    Messages: 2,243

    You know it might just be simpler to use your relays and activate them with a switch on your dash like Boss does. Putting the LED bulbs in may reduce the power used on the plow but would you want to just hook them up in parallel with the truck lights? It really sucks to have the truck lights shining back in your eyes when they shine on the back of your blade. That's why they are switched off by the relays / isolation module. You could just use the original headlight power, direct it through four relays, one for each bulb, and then switch the relays from truck to plow by powering or disconnecting the coils of those relays with a switch. As long as the truck is a few years old the change in current draw would not be a problem. If it is a later model with current sensing you could add two more "isolator relays". Connect one relay coil to activate with high beam and one to activate with low beam. The coils would draw very little power and then connect the normally open output from battery (through a fuse) to your secondary plow / truck relays. This way the difference in power draw between the two headlight systems would not be sensed by the vehicle. Just an idea.... In effect this is what the isolation modules do.
     
  10. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    Misnick,

    The connections are all compatible and number the same for my truck.
    I read on the link page 11 from Basher, that implies I could simply ensure I turn the headlight connection appropriately to match whatever load switching my truck is, which I will determine for sure tomorrow in daylight. (Would that not address the positive/negative switching issue, rather then re-configuring the relays?)

    In Canada, all vehicles from way back have to have DRL's, so would I not be able to bypass that connection on the harness, as the headlights come on regardless of however you try to use the switch inside the vehicle?

    I will work on it tomorrow, and see how it makes out.....if there are too many issues I will just wire in new connections in each headlight/turn signal and unplug from truck (in an accessible area of course) and in to plow lights when mounting the plow. Will just have to open the headlight covers on the plow assembly to trace the corresponding wires back to exposure near relays on the harness.

    Thinking from way back in my past, even if the headlights are switched oppositely (neg load as opposed to pos load) would not the relays still operate the lights regardless, being dc? Meaning ground is still negative (as it would have to be as the truck/plow are) and the switching is (would) be still doing the same thing?

    Heard that Alberta got some cold weather moving in the past few days.....endless winter on it's way??
     
  11. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    I will complete the harness install as the western manual provides and see if anything takes place....and if nothing happens I will turn the plug in connections over and see if that makes a difference. If not, I will either wire in a switch/relay as you said, or use the existing connections on the harness and wire in interuppted plugs from the vehicle lights (as you said so I don't get the lights shining back on me).
     
  12. mishnick

    mishnick 2000 Club Member
    Messages: 2,243

    Not knowing your circuit by heart I can't really answer your question well. I know that the relays could be made to work on common Pos or common Neg. Just a matter of switching some wires on the coils of the appropriate relays. Sounds like you are pretty strong with you electrical so I think you should dive in an show us how smart you really are.

    As for endless Alberta winters..... I only wish... Being a snow plow mechanic and a plow operator I see snow as white gold falling like manna from heaven. Send us all the moisture you have to spare my friend, we will provide the cooling and turn it to snow. Last winter I only plowed SIX times!!!!!! This year I need to do more than pay my liability insurance.
     
  13. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    I did little snow last year here in Toronto area as well....it was brutal! Had a smaller plow and didn't mount it once......they say this winter will apparently have more snow "events".....we'll see.
     
  14. mishnick

    mishnick 2000 Club Member
    Messages: 2,243

    Well you know if the Stampeders win Grey Cup tomorrow they are going to light the flame on the top of the Calgary Tower.... So I am torn.... I want our boys to win so we have an excuse to party but I am afraid when they light the tower all the snow will melt! Oh well, there will be more snow after the flame goes out. Good luck to you guys in "Trona"! I was actually born near there in a little town called Tavistock, near Stratford & Kitchiner / Waterloo so I think I will be happy no matter who wins. Still have lots of family & friends there.
     
  15. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    Harness is in, plow functions in all ways. Lights function almost completely....
    the only function missing is high beam. When I switch inside the truck from low to high beam, the plow lights go out. So, I think I will leave it as it is for now. (am going to switch light connectors from having low beam working, to having high beam working and aim the lights down a bit.)
     
  16. basher

    basher PlowSite Fanatic
    from 19707
    Messages: 8,992

    Check your grill connectors for rotted or missing pins. I know it's a long shot but do you have two burned out high beams on the plow? Check the wiring configuration on the high beam relay.
     
  17. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    I haven't yet checked the pins or the bulbs but will do so in the morning. I didn't mention that when lights are put in high beam, the plow lights drop to DRL. So, I think that's to be a correction in the relays. When I look at both schematics for 99-02, and the 03 up, they are completely different, with leads coming in to the 03 which are not available (listed or described) for the 99-02 configuration. I will play around a bit tomorrow, but I don't really want to clear off all 6 relays and restart. I can make do with utilizing high beam and lowering the angle....might annoy a few folks though...., at least switching the indicator lever inside the truck drops the opposing beam to DRL, so that may be the way to stay if I can't readily find a fix.

    Thanks for the link and help Basher. (and Mishncik)

    Internet has been a blessing.....found out about many issues and related repairs for my trucks, much to the chagrine of the stealers......and when you question them about recalls/faults, they pretend that they have never heard of what you mention.....for my g.m.'s, pump clip rub is the main scam.....as is their marginal braking systems they put in.....both apparently heading to class action suits in the u.s., but here in Canada we don't have the sales of units to force what the u.s. consumers can do.
     
  18. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    Update.

    I checked the bulbs, and the harness. There are 9 pins used of the 12 pins in the connector. I couldn't see any broken or corroded pins and the bulbs are good.
    I could try to trouble shoot and rewire the relays, however the schematics from western indicate a much different layout between the seperate year designations and as I mentioned before, a couple of leads come in that are not listed in the schematic for the older harness I have so will leave it as is.

    So, everything works aside from the high beam. Now if anyone finds a plow with 99-02 sierra/silverado wiring, we know it can be used as is to mate up for 03 onwards with the exception of high beam.

    Thanks for the help received, I appreciate it.
     
  19. brad96z28

    brad96z28 PlowSite.com Addict
    Messages: 1,526

    Yes they all work if they have the same stlye headligt connectors. you switched the wires on the high and low beams correct? If you only swapped the wires on the low beams only the low will work.
     
  20. oakridgedriver

    oakridgedriver Junior Member
    from d
    Messages: 14

    I initially tried to swap connectors, but they have a single or double guide to prevent that. So I swapped connections inside the headlamp assembly but it didn't do anything as far as I could tell, in regards to brightness. I haven't done anything else at this point. I will look over the schematics to see what could be altered, but with the DRL being promtped by switching to high beam inside the truck, that indicates to me the relays have to be reworked, likely all wires re-routed....I will look over the schematics, to see if I can swap a few wires and end up with high beam, and DRL. I would rather have the high beam and simply flash down to DRL when approaching other vehicles on the highway, but can live with low beam.