I acquired my fathers 1971 Bronco a few years ago - introduction posted in another thread. I've finally had some time to work on it. He installed a Centech wiring harness in the mid 90s. Then through the years, he had it at a garage occasionally for issues. I'm impressed with Centech's harness and appalled at the work the shop did. So, I removed everything that didn't belong and went back to a stock-ish setup using the Centech harness. I installed a stock ignition/start switch, installed a missing hazard switch, and installed a cigar lighter. All this was clearly marked on all the wires. Everything works flawlessly, including the turn signals now (ya!) and even the hazard switch works as it should (ya!, the wires were previously taped up in the dash), heater, windshield wipers, and whole nine yards. Everything. Important to note is that the turn signal indicators in the cluster work as they should. Given how nasty it is to get the headlight switch out, I installed a new Centech style headlight switch while I was there.
Until... I turn on the headlights. Everything exterior works as it should (all lights, running lights, headlights, low and high beams, turns signals and brakes - ya!). The left cluster illumination light works as it should (nice and bright). However, with the headlight switch in running lights only or with the head lights on low or high beam:
1) the top and right cluster illumination lights are 1/2 bright on the running setting and full brightness with the headlights on.
2) Both turn signal indicators lights are on and bright, and blink off when I use the turn signals.
3) The high beam indicator is always on, regardless of headlights off (running position), high or low beams.
IF, the one cluster illumination light didn't work correctly, I'd say it was a ground issue with the cluster case. However, the Centech harness runs separate ground wires to all the bulbs in the cluster and then ground at a common location on the body. However, it does seem like a ground issue to me. I do see that I ran the wire the wrong way through the amp gauge coil as it's reading backwards. That's an easy fix.
Any suggestions? Changing out the headlight switch is going to be the last thing I try. I'm 6'4" and 240 pounds. I barely fit in the seat - getting under that dash is pure hell. There is no wiring diagram that came with the Bronco and Centech did not use any common wire colors - however, again, the wires are all clearly marked with names. The Centech Installation Manual and Information Pamphlet that did come with the Bronco are not very helpful. I'm going to pop out the hazard switch and disconnect it as that is really the only new variable added to the harness. ???
Any suggestions?
Thanks,
Al Jones
1971 Bronco
Brookings, SD
Until... I turn on the headlights. Everything exterior works as it should (all lights, running lights, headlights, low and high beams, turns signals and brakes - ya!). The left cluster illumination light works as it should (nice and bright). However, with the headlight switch in running lights only or with the head lights on low or high beam:
1) the top and right cluster illumination lights are 1/2 bright on the running setting and full brightness with the headlights on.
2) Both turn signal indicators lights are on and bright, and blink off when I use the turn signals.
3) The high beam indicator is always on, regardless of headlights off (running position), high or low beams.
IF, the one cluster illumination light didn't work correctly, I'd say it was a ground issue with the cluster case. However, the Centech harness runs separate ground wires to all the bulbs in the cluster and then ground at a common location on the body. However, it does seem like a ground issue to me. I do see that I ran the wire the wrong way through the amp gauge coil as it's reading backwards. That's an easy fix.
Any suggestions? Changing out the headlight switch is going to be the last thing I try. I'm 6'4" and 240 pounds. I barely fit in the seat - getting under that dash is pure hell. There is no wiring diagram that came with the Bronco and Centech did not use any common wire colors - however, again, the wires are all clearly marked with names. The Centech Installation Manual and Information Pamphlet that did come with the Bronco are not very helpful. I'm going to pop out the hazard switch and disconnect it as that is really the only new variable added to the harness. ???
Any suggestions?
Thanks,
Al Jones
1971 Bronco
Brookings, SD