Relay identification (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Dec 29, 2024
Threads
5
Messages
29
Location
Texas
Can anyone please tell me which each of these relay ports correspond to?
IMG_0019.jpeg
 
There were 3 relays that were plugged into 3 of the ports. The relay part number on all three is 90987-02004. Same as the efi relay.
 
You need to let us know year/model.

This is from a 1991.

1743292001269.png
 
91 should use the same diagram as my 92 but it looks different. I have 4 more locations for 4 pin relays across the top of the block.
 
The whole reason I’m down there is because I’m trying to find my efi relay that the PO moved away from the fuse block that’s in the engine bay.
 
1991 is showing only "Cooling Fan Relay" and "Blower Relay High" for those top 4 locations.

Someone moved the relay? 🤦

It might be near the ECU as that is where power sent. Lift up that engine bay relay box and see if it is nearby, otherwise it could be near the ECU.
 
Alright so 2 of the locations are just blanks i guess? & yeah they moved it 🤦🏻‍♂️ I pulled the glove box and checked around the ecu and behind the passenger side kick panel and nada. Don’t know where the hell it could be. Was hoping they relocated it to the block that i was asking about but i pulled every single relay and the vehicle still fired right up. If the efi relay was one of those that i pulled it shouldn’t have fired up right?
 
they could have hardwired it.

I would check to see if there is power downstream of the original location EFI relay when the key is off.

I only have the 1991 EWD, so the wiring colors might be different.

You want to look at EB1 connector, which is a connector behind the relay box in the engine bay.

1743295761508.png


Check voltage at pin 3 (Y-R). This would be after the relay. You should have 0V if the vehicle is off. It should be 12V if the vehicle is on.

if the PO did indeed move the EFI relay, you might not see voltage there.

You should always have 12V at pin 2 on the EB1 connector. The 1991 EWD doesn't show another connector, but I think IH1 might be involved...

1743295601443.png
 
Last edited:
alright I’ll be checking that tomorrow. Thanks man!!
If the EFI MAIN relay was jumped to be always on, the battery would drain down overnight, as all of the sensors would be getting +12.
 
Soo i found what looks to be an aftermarket 5 pin mounted on inner fender behind the fuse box, not sure what it is bit i do know the vehicle wouldn’t start once i unplugged it. The wires run back to the same loom that comes out of the fuse box.
 
Am i correct in my assumption that it’s aftermarket? And if so, is there any way in hell the PO could used a 5 pin relay as the efi relay? Because i can still not track down the efi relay itself.
 
Nvm it’s definitely the efi relay. Pulled back the bs tape they used and it actually only has 4 wires to the relay & they match the color scheme of the efi relay. Not sure why the po didnt just use an oem relay but that’s neither here nor there.
 
I figured it would be behind that relay box. Thats a lot work to avoid paying the OEM price bump for an OEM relay...
 
I figured it would be behind that relay box. Thats a lot work to avoid paying the OEM price bump for an OEM relay...
Yeah i noticed it yesterday but when i looked at it and saw 5 wires coming from it i automatically ruled it out as the efi relay 🤦🏻‍♂️ lol
 
Guess i need to pull my gauge cluster and see if my check engine light was pulled by PO or if it blew out. Still not getting a check engine light after replacing the relay.
 
Guess i need to pull my gauge cluster and see if my check engine light was pulled by PO or if it blew out. Still not getting a check engine light after replacing the relay.
Iirc, there's a test point for that in the diagnostic connector.
 

Users who are viewing this thread

Back
Top Bottom