Brett mentioned …
“I don’t think color has anything to do with it, only thing that counts is
if the relay has a diode across the coil, you need to replace it with one
that has the diode.”
Good advice on ensuring the addition of a reversed biased diode across the
relay coil … at least on a circuit controlled by some form of electronics.
But on “most” XJ40s, I would think its likely not required as the “reversed
biased diode” for the relay coil is installed within the wiring harness
itself. But, of course, if you are adding new circuits … good idea to
consider the installation of the diode.
There may be a “color code” for relays … at least maybe for Hella. My
XJ40 has green, yellow, and black colored relays. Hella seemed to be the
supplier of choice at the time of vehicle manufacture. The all seem to have
similar electrical characteristics … 30 amp contacts and 75 - 90 ohm coil.
The only difference I’ve noticed is “contact configuration”. One color
seemed to represent a relay with only a normally open contact ( 4 spade)
while the other color represented a relay with both normally open and closed
contact configuration (5 spade). The only “black” colored relay I can
remember seeing was for the Teves pump motor … which happened to be a
higher current capacity relay (40 amp) as well.