How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask K. Wiggins Your Own Question
K. Wiggins
K. Wiggins, Technician
Category: GMC
Satisfied Customers: 2642
Experience:  ASE Certified Technician AA in automotive technology. 15+ years in the automotive field
Type Your GMC Question Here...
K. Wiggins is online now
A new question is answered every 9 seconds

I have a 1991 GMC Vandura, it has hologen lights, it keeps

Customer Question

I have a 1991 GMC Vandura, it has hologen lights, it keeps flickering and not getting full power to the lights. what do i need to upgrade the Light wire harness. and need the steps to do so. Thanks
Submitted: 10 months ago.
Category: GMC
Expert:  Ron replied 10 months ago.
Hello, my name is ***** ***** I am a professional here at Just Answer. I have noticed that your question was not getting a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.There is no reason why you would need to replace the wiring providing its not damaged. I would start first with checking the voltage at the head lamps when the problem is occurring, your voltage readings should be battery voltage with the lights on and also hold steady. If the voltage checks okay the the next step would be to check your ground, the black wire is the ground wire to both the theft and right sides. Start with making sure both sides are getting a good ground. Check these things for me and post back with the results and we can work from there.
Customer: replied 10 months ago.
Thanks, ***** ***** busy at work. I just need to know what i need to buy to just replace and update to Light harness, she's 25 years old and needs a replacement. Just need what to buy and how to install it. I think theirs a whole Wire set for it. with relays and whole set with everything just need to connect it with the old Pull relay on the dash.
Expert:  Ron replied 10 months ago.
Unfortunately with out checking for power and ground Im not sure what you need to buy. I will open the post back up for you and perhaps someone else will know what you need.
Customer: replied 10 months ago.
Sounds good thanks.
Expert:  K. Wiggins replied 10 months ago.
Hello, I'm familiar with the kits for the lighting upgrade and how to wire it in. What type halogen bulb did you upgrade to? H4, 9004, 9003 etc? or did you just upgrade the sealed beam?
Customer: replied 10 months ago.
Its a H4, the replaceable type. Sorry for the late response. have been Working alot lately.
Expert:  K. Wiggins replied 10 months ago.
No problem this is the harness you'll need. That one plugs right into your current connectors and you just have to run the power wire for the relays which you can connecto to the positive battery terminal or output post on the alternator.
Customer: replied 10 months ago.
And how do you assemble using the old set just like it. I have 4 head lights, 2 HIgh and low, and 2 High only. Don't know where to start.
Expert:  K. Wiggins replied 10 months ago.
i'm a little confused are you asking about the dual filiamnt H4 or converting over?
Customer: replied 10 months ago.
I have bought the H4 Headlights, the old wire light harness is old and not able to fully optimize the lights fully. i need to know what to buy to replace them, and how to do it.

Related GMC Questions