mr_manny
Well-Known Member
- Joined
- Dec 1, 2024
- Messages
- 115
- City
- Mexico
- Vehicle Year
- 1990
- Transmission
- Manual
- Tire Size
- 235/75R15
I noticed this when I received my new-to-me 1990 Bronco II.
Wiring to ECC relay:
Notice both original red wires are joined, original black is yellow, original yellow wires are joined and now green.
The RED wire isn't even connected.
The universal relay is only connected with the original black and yellow wires.
The vehicle made an 18hr journey, so I figured it could simply add it to my todo list.
I've been going through my list, changing fluids, replacing wheel cylinders, bypassing the RABS module...the usual stuff
The other day the Bronco wouldn't start, so I through it on a 2a charge...everything is back to normal the following day. The battery is new, so I started thinking about possible causes.
I started to look for a parasitic draw, and noticed a click when I would connect the negative battery cable. The single click (when connecting the battery) is coming from the universal relay (ECC replacement). I also noticed the universal relay was slightly warm to the touch.
When I was cleaning out the interior, I did find an original relay with brown connector.
Is there a way to test the relay, before wiring it back under the hood?
The yellow wires are the only ones that have continuity.
Any assistance would be appreciated.
Wiring to ECC relay:
Notice both original red wires are joined, original black is yellow, original yellow wires are joined and now green.
The RED wire isn't even connected.
The universal relay is only connected with the original black and yellow wires.
The vehicle made an 18hr journey, so I figured it could simply add it to my todo list.
I've been going through my list, changing fluids, replacing wheel cylinders, bypassing the RABS module...the usual stuff

The other day the Bronco wouldn't start, so I through it on a 2a charge...everything is back to normal the following day. The battery is new, so I started thinking about possible causes.
I started to look for a parasitic draw, and noticed a click when I would connect the negative battery cable. The single click (when connecting the battery) is coming from the universal relay (ECC replacement). I also noticed the universal relay was slightly warm to the touch.
When I was cleaning out the interior, I did find an original relay with brown connector.
Is there a way to test the relay, before wiring it back under the hood?
The yellow wires are the only ones that have continuity.
Any assistance would be appreciated.