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TR4/4A Another horn problem

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carpecursusII

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OK, I think I've been through it all and still they don't honk. I know that I have power at the solid purple wire(fuse is good as well), I have good continuity on the purple/yellow, black, and the purple/black wires. I have tried to bypass the entire steering column by going direct from W1 on the relay to ground and got nothing. I have tested the relay and have 72 ohms of resistance between C1-C2. When I put power between W1 and W2 the relay clicks.

I've been thinking, the overdrive on these cars uses the same 6RA relay, on the overdrive there is power to one side of the W1/W2 and the other side goes to the switch and off to ground. On the horn only one side of the W section is connected to anything, to me this makes no sense.... Can someone tell me what I'm missing here or why it doesnt work.
 
carpecursusII said:
I have tested the relay and have 72 ohms of resistance between C1-C2. When I put power between W1 and W2 the relay clicks.
Click to expand...
Should be totally open circuit without power applied to W1-2; a dead short with power applied.
On the horn only one side of the W section is connected to anything, to me this makes no sense.... Can someone tell me what I'm missing here or why it doesnt work.
Click to expand...
You're right, that makes no sense at all if it is really the same relay. Not all 6RA relays are necessarily the same; and I believe the horn relay should have only 3 terminals (Lucas P/N 33188 instead of the 33213 for the OD). With the horn relay, the other side of the coil is connected internally to C2.

UNTITLED.jpg~original


For a quick test, you could just connect a temporary jumper between the purple wire and the vacant W terminal.
 
I chased around my horn for a long time, checked the fuse several times. The last time I checked and changed it, fixed it. Maddening.
 
The jumper from C2 to W2 solved it. I had to jumper both the old 33213 relay (which makes sense given the design) and the new relay that moss is selling as a replacement (Lucas 26RA)
 
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