1970-71 Horn Relay Wiring

[Pat Bush]

Hello all --

I have a bit of a quandry here.... I have a 1970 coupe and a 1971 convertible I just purchased. the ammeter does not work on the 71 but does on the 70. After reading through the service manual and tracing a bunch of wires I ended up at the horn relay. Unfortunately, I see the the wires, but the diagram does not show where to hook them up....

The wiring is reversed on the 71 as opposed to what is on the 70. The 70 was just professionally restored so I am assuming this is correct, but I wanted to verify and see if there were any changes in 71.

The 71 is wired:

BAT Terminal - Fusible Link, Large booted 10ga? Red wire (goes into harness)
Other Terminal - Two Red wires 12GA and OR/BL wire

The 70 is wired:

BAT Terminal - OR/BL wire
Other Terminal - Fusible Link, and two red 12Ga wires

Now, the horn works fine on both as does the iginition buzzer. I seem to have an extra BIG red booted wire on the 71 that is not on the 70. The ammeter works on the 70. The harness on the 71 is original. The harness on the 70 is a lectric limited. Both cars have AC. The 71 also has power windows.

Which one is correct?

Sounds like a test question doesn't it :-) Any help here would be appreciated. Both cars run great but I am thinking something is rotten in Denmark.....

Thanks in advance -

Pat

[John H.]

Re: 1970-71 Horn Relay Wiring

Pat -

Makes no difference; both screw terminals are on the same common 12-volt bus at the relay. The ammeter is really a shunt voltmeter that reads the difference in voltage between the big starter solenoid stud and the bus on the horn relay (which is where the two wires go from the back of the ammeter, through the fuse block firewall connectors) and displays it as "amps", although it's not really measuring current flow like it does on C1's. Check the small wire at the starter stud and continuity of both wires through the firewall connectors.

[Pat Bush]

THANKS, John!!! *NM*