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69 Horn Relay Has a 65 Ohm Short To Horn Button

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Old 11-09-2018, 10:47 PM
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jpatrick62
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Default 69 Horn Relay Has a 65 Ohm Short To Horn Button

Chasing down (yet another) electrical malfunction in my 69. Looks like I have a 65 ohm Short to Ground from the black wire that connects to terminal 3 of the horn relay. When I disconnect this wire from the
horn relay, the 65 ohm short across my (disconnected) battery cables disappears, so I know I am onto the issue. Question - does the horn contacts in the steering column connect the #20B (Black) wire to ground when
you push the horn?
Old 11-10-2018, 12:02 AM
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7T1vette
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The 65 ohms is probably the impedance of the relay coil. Lots of fine wire in those coils. Check that continuity across ONLY the relay connections to determine if that is the case. You can't get near ZERO ohms in a string with a coil in it.
Old 11-10-2018, 09:55 AM
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jpatrick62
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Yeah it's 65 ohms resistance to ground from the black wire (disconnected from the relay) that goes into the firewall and then presumably to the horn button. When I first
got the car the wire was disconnected from relay and I thought it had fallen off. I suppose the last owner took it off for this reason.
Old 11-10-2018, 10:52 AM
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henrikse
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Take that reading with the harmonic connector (long one bottom of steering column)disconnected to further isolate? Either in the column or wire to relay. There is a plastic insulator in column that may be incorrect or ribbon cable rubbed thru a bit
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Old 11-10-2018, 06:16 PM
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DUB
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Originally Posted by henrikse
Take that reading with the harmonic connector (long one bottom of steering column)disconnected to further isolate? Either in the column or wire to relay. There is a plastic insulator in column that may be incorrect or ribbon cable rubbed thru a bit
I agree. This circuit is easy to repair but serving what may be wrong with it may require getting into the column.

DUB
Old 11-11-2018, 11:00 AM
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jpatrick62
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Yeah, most likely it.s in the column but I'll isolate further by opening the connector. I will have to replace the horn button in the steering wheel anyway since even with the wire hooked up the horn only worked if you hit the horn a certain way on the wheel. Just have to budget carefully on this project and since the front suspension is more in need this fix will wait until spring.

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