Question on hooking up a relay

I have a relay that is not working on a 1954 car. I am attempting to replace it with a modern relay. Could anyone please tell me which of the modern designations (30, 85, 86, and 87) match up to the terminals on the original relay (UB, LB, BAT, and C)? Thanks for any help on this. Jim

 

what kind of a relay is it? what kind of a car is it? can you take the cover off the relay? or tell us what the circuit is that it's used in?

most modern relays have a diagram showing which terminals are the coil, and normally open or closed contacts.

 

It is an aftermarket 4 prong relay with 30, 85, 86, and 87. Which of those relay terminals is the battery; which of those is the ground and which of those is UB; and which of those is LB?

 

30 is battery voltage. 85 is ground. 86 is switched (usually key-on power). 87 goes to the device you wish to operate. horn, light,etc. Good luck. Oh, and sometimes the 87 and 87a terminals will either both be hot together, or will alternate when the relay is powered up. Look at the diagram on the relay body to see what you have.

-Greg.

 

What Squirrel said, we need more info as to the original use. Not all relays are interchangable. Overdrive relay? Converting to 12 volt?

 

We have no idea what UB and LB are, we need to know what you're working on.

 

I think the OP is being way too vague in the search for help.

What kind of car, and what is the relay for, OP?

 

May be a second the ub is battery and the lb is the load