4.0 wiring harness install

[stamina]

after installing the 4.0 harness from a 92 explorer into my 90 ranger i’m having a few issues, first off, green dash lights won’t come on, blower motor does not work, radio does not work, check engine light is on but is very dull but the other indicators (red brake and orange rear anti lock) work fine and the headlights/running lamps are doing some odd things, the turn signal lamps are on at all times as soon as you hook up the battery and they work when you flip the turn signal switch but don’t turn off when you i flip the switch, and the head lamps are staying on but very dull. they will turn on full brightness with the switch but when cut off they stay on and very dull. the only difference between the harnesses was the large square connector that went back to the chassis wiring that i modified and turned it into 2 circular connector to match what my truck originally had, so that’s good. and the small harness that goes through the fire wall next to the computer harness was different, had two connector in the engine bay that mounted to one of the blower motor bolts, what looks to be a relay, and the connector on the inside is a blue female and doesn’t have the second connector like my original one did, i tried using the original to begin with but it didn’t work, so i tried hooking the blue one up to original connector in my truck and splicing in the wires and that also didn’t change anything i’m very confused. brake lights work, windshield washer pump works , rear turn signals work, dome light works, cargo lamp works, other things have not been hooked up yet such as alternator, ac compressor, fuel pump, and anything else attached to the engine as it has not yet been put in the truck. plz help.

 

[RobbieD]

Check and confirm ALL of the wiring grounding points and connections first.

 

[stamina]

Check and confirm ALL of the wiring grounding points and connections first.

the only one that’s not connected is the cylinder head ground. but i will go over my work tomorrow and make sure everything checks out

 

[Northidahotrailblazer]

I thought the big round plug was pinned differently in the explorers than the rangers? Its been many moons since I was schooled up on this, but that is one of the differences in the explorer harness. If you had a ranger harness then it would be plug and play. But you have to do repinning if i remember correctly. Look in the tech section here 89 bronco 2 to explorer swap. I'm pretty sure its there.

 

[Northidahotrailblazer]

scratch that. I think all you have to mess with are the plugs on the fender not the main dash bulk head plug.

 

[stamina]

scratch that. I think all you have to mess with are the plugs on the fender not the main dash bulk head plug.

yea i repinned the whole connector to two connectors that matched what was already coming from my harness under the truck, repinned it into the original two and color coded it, i’m having issues with the interior stuff and headlamps, the other difference is the other firewall harness that goes to the two plugs under passenger side dash, the one from the explorer has one plug on it and a vacuum line and the, is the easiest way to remedy this by getting the dash harness from the explorer and not using the power seats, locks, and rear defrost? original has two plugs that plug right up but it doesn’t change anything.

 

[Northidahotrailblazer]

I think you should do some reading in the tech section. I just can remember anymore. Have you started the 4.0 yet?

 

[SenorNoob]

Definitely sounds like a grounding issue to me.