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Headlights

Discussion in 'Fisher Engineering Discussion' started by hbrady, Jan 14, 2016.

  1. hbrady

    hbrady Senior Member
    Messages: 221

    So with no snow in the extended forecast I pulled my MM2 plow off my 2014 Silverado tonight. Normally when I pull the plugs the truck headlights come on but tonight they didn't (and yes, it was dark). I tried turning light switch from auto to on and no luck. Only after I backed up a few feet did the truck headlights come on. Any ideas?
     
  2. hbrady

    hbrady Senior Member
    Messages: 221

    Interesting development tonight. Keep in mind this is a 2 year old truck and plow and yea, I put dielectric grease on pins in plugs. So tonight, I went to hook plow up, when I plugged in the harness on the left the truck switched to plow lights but only one headlight came on. I pulled plug and plugged back in, this time neither headlight came on, just parking lights. I messed with light switch, turned truck off / on and after about 30 seconds both plow headlights turned on. Any ideas? Solenoid going bad? If so, pretty sad.
     
  3. dieselss

    dieselss PlowSite Fanatic
    Messages: 10,968

    Solenoid has nothing to do with it.
    Might be ground issue or the plow plug.
    Warranty?
     
  4. hbrady

    hbrady Senior Member
    Messages: 221

    Second owner :(
     
  5. hbrady

    hbrady Senior Member
    Messages: 221

    Checked all wiring, everything is clean and tight. What's strange is that the delay in swap seems to be getting progressively longer but once swapped everything works fine. The isolation module controls the swap right? I guess I'll go see my local Fisher dealer. I'm checking with original owner but I think plow was purchased in Feb 2014 so hopefully they will honor warranty with 2nd owner.
     
  6. dieselss

    dieselss PlowSite Fanatic
    Messages: 10,968

    Yes the Iso controls the plow lights with the proper inputs.
     
  7. RepoMan207

    RepoMan207 PlowSite Fanatic
    from Maine
    Messages: 5,033

    Have you checked the wiring truck side...beside the grill connectors...plugins to the ISO and behind the headlamps where the fisher wiring ties into the truck's harness? I'd even pull the fuse under the hood to make sure it's seated fully and in ok shape.

    I've found dielectric grease to only compound a problem if you don't first clean the ports thoroughly...and even over greasing them, I go as far as using a small pick and a healthy dose of brake cleaner in each socket before even inspected or adding grease. If it's cold and you don't have a heated garage, boil some water, and bring it out in a bucket, with everything off, and the key out of the ignition, put the grill connector right in the water and swish it around vigorously, get it all softened up and then go at it with the pick and brake cleaner to restore to new condition...all, plow and truck side.

    I'm local if you run into an issue, just let me know if you need a hand with it.
     
  8. Philbilly2

    Philbilly2 2000 Club Member
    Messages: 2,595

    Hey bud, you think this could be a relay in the iso box hanging up? I have not heard of that issue exactly per say, but I have had the old style relays hang as they start to age. Just kicking ideas as this is an interesting one...
     
  9. dieselss

    dieselss PlowSite Fanatic
    Messages: 10,968

    It could be......
    I personally think it's corrosion somewhere.
    IF the internals are just relays and they are the 5 pin kind, as soon as you take away signal power or ground, the relay diverts back to 87a. So, I'm thinking that something is not telling the Iso that the lights are/aren't connected anymore.
     
  10. hbrady

    hbrady Senior Member
    Messages: 221

    Thanks Ryan, I have checked the wiring pretty thoroughly and it's all like new and tight; however, I have not looked at the plugs very closely. I tend to agree the behavior points to a bad connection, especially the one time when only one of my Intesifires lit up. I'll try cleaning the connectors and see if that helps. I pulled the plow last night and it took about 90 seconds for my truck lights to kick it. It seems each time this happens it's getting longer.
     
  11. hbrady

    hbrady Senior Member
    Messages: 221

    OK, here goes. Cleaned both sides and they look like new (pics below). Plugged in the plug, heard iso click, parking lights came on, no headlights. Messed for 2-3 min getting my minute mount mounted in the dark. Got in cab, moved to garage, played with light switch, nothing. Turned high beams on and they worked, when back to lows, nothing! Took out my phone to type notes and after another minute headlights came on. So, 1st time this happened 30 seconds, next time, a minute, next time 2 minutes, now we are up too a solid 5. Same in reverse when I remove the plow. Lights will work 100% of time until I remove plow but next time, may be 7-8 minutes before truck lights come on. I'm an IT guy so I know a little bit about electronics.. I'll bet $10 iso is going bad. Any takers?

    I'll make an appointment at Messer tomorrow, thanks all for the feedback, I'll keep you posted..

    cp1.jpg

    cp2.jpg
     
  12. hbrady

    hbrady Senior Member
    Messages: 221

    Almost forgot.. before I moved to garage I opened hood, played with the wires / connections and gave the iso a couple friendly taps.. nothing.
     
  13. RepoMan207

    RepoMan207 PlowSite Fanatic
    from Maine
    Messages: 5,033

    I suspect it's the ISO, Bob will take forever getting you in. Let me know, I might have a green label ISO downstairs you can try.
     
  14. hbrady

    hbrady Senior Member
    Messages: 221

    great, thanks!
     
  15. hbrady

    hbrady Senior Member
    Messages: 221

    So here is what I found out. Called the original dealer who was very helpful. Turns out my truck was one of the first 2014 Silverados they did, before Fisher realized the new model Silverado engine compartments run very hot. They redesigned the iso and instructed dealers to install it on the inside of the fender wall. He's faxing me proof of purchase / install from March 2014 and said Fisher will stand behind it and replace it no questions asked. He agreed the iso is cooked. I'm waiting for Bob to call me back and see if they can squeeze me in, I'll let you know how I make out Ryan.

    By the way, anyone in the the Lancaster MA area looking for a fisher dealer should give J.C. Madigan a shot. They were VERY helpful and even apologized for my trouble. They will be getting a Google and Yelp 5 star review from me.
     
  16. dieselss

    dieselss PlowSite Fanatic
    Messages: 10,968

    Good customer service right there
     
  17. Yup you're gonna need the purple(violet) label soft stop iso mod. I had to swap mine when I swapped by XV from my '04 to my '15.
    I think the P/N is 29760-1
     
  18. hbrady

    hbrady Senior Member
    Messages: 221

    Getting the iso replaced next Friday.
     
  19. hbrady

    hbrady Senior Member
    Messages: 221

    Well.. I jumped the shark. Been looking to trade and I just pulled the trigger...MacDonald's gave me a good trade number and they will replace iso.. but it's not longer my problem :mechanic: Just the big freaking payment is :drinkup:

    Picking her up in an hour

    RAM.jpg
     
  20. Trading a Chevy for a Dodge???? OMG...the sacrilege!