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4.0 conversion electrical issue


Thaner46

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I am in the midst of doing a 4.0 conversion from my 1992 ranger stx 4.0 4x4 5speed into my 1990 ranger xlt 2.9 2wd 5speed. No problems getting the engine in and hooked up and got it running but my instrument cluster doesn't work, the turn signal indicators and high beam indicator are alway on(even when the key is off) the radio is alway illuminated and I have no brake lights. Other than those problems it seems to run great. But I have no idea where it went wrong. Where should I start? There is one wire that the 4.0 harness doesn't have in it and it runs into the cab it is gray with blue stripe, have no idea what is it for?
 
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wynnespeed

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recheck ALL of your grounds
 

SenorNoob

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The only Gray/LT Blue I see should run from the O2 sensor to the computer. That shouldn't go into the dash.

Shouldn't this have been a plugin swap?

I second the grounds statement!!!
 

Thaner46

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I checked the grounds, I even went as far as to replace both the interior and exterior harness and the same problem. Turn signal indicator and high beam indicator as still illuminated
 

SenorNoob

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Just an idea, but what happens if you disconnect the wiring to the cluster? I think there were some pin-out changes over the years.
 

Thaner46

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Ya when I disconnect the cluster the lights go out cuz there's no power but when it is plugged in I tried pretty much everything to find out where it is coming from. I disconnected the multifunction switch, light dimmer switch pretty much everything in the interior. And I replaced the exterior harness, I thought for sure there was a short somewhere in the harness but that's not the case
 

Thaner46

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But the lights still won't go out. The only way they go out is when I take the bulbs out
 

SenorNoob

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Could the cluster itself be bad?
 

adsm08

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Main light switch.
 

Thaner46

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It's not the cluster cuz I replaced it will the one form my previous truck. And I unplugged the main light switch and the lights on the cluster remained on
 

adsm08

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Well if you replaced both harnesses I doubt it's a wiring issue. That leaves us with components.
 

Thaner46

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Ok. Ya I'm gonna see if I can get some parts this weekend, but I tried pulling the fuses out to narrow it down and they still wouldn't go out even after I pulled them all��
 


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