My 420 came sans horns. The po had not worried about it but I live on a crazy busy highway (bloody 98) and feel the need.
I have mounted a set of horns but do not see any relay.
Can I get a location, or picture of the stock relay location.
The parts book and manual have a close up of the location, but I can't make out if it is a wing or firewall???

pls n thx

 

If it follows S Type convention, which I think it does, it will be right at the front of the RHS inner wheelarch. Otherwise check front LHS wheelarch.

Agree this is not the most helpful diagram. Hopefully a 420 owner will chip in.

 

As Glyn has stated on the S Type the relay is located on the inside of the front wing in the engine bay just behind the radiator and above the brake servo. Difficult to photograph so I have gone back through my assembly and disassembly photos and found these two which might help.

 

The standard position on a Mk2 (when fitted) is adjacent to the fuse box. However, I'm sure that I've seen one near the slip ring connections on the steering column. That may well have been an owner upgrade.

 

The connector you see above it in the diagram & 2 earth loops are the lighting connectors for the sub-harnesses that go the respective units headlights, sidelights, flashers etc. for one side. Not yet fitted here. Taped wires here.


Horn Relay




420 Harness layout



I think what you see to the left of the diagram is supposed to be the Saginaw PS pump & drive.


Earth connector above main lighting connector block.

 

in both my 1965 S type and my 1984 XJ-6, the horns relay is mounted on the left inner wing as you stand in front of the car looking at it, Behind the radiator halfway down in both cars. Check the fuse, those relays rarely go bad.