The horns have stopped working on my 55. They were intermittent before
No voltage at the horns themselves
next step according to the shop manual.....check the horn relay .....I can't find it. Manual indicates "engine side of the dashboard " whatever that means ? Doesn't tell me how to check the relay .
If it's not that it's suggested that it's the horn button. Any suggestions with that task?
Thanks
Al
Relay. Don't bother with the repro ones as they don't work as well as a good NOS will.
It is located on the radiator core support backside
Keep Cruzin,
Bob Kielar
The horn relay is right below and right of the voltage regulator. See pic. It has three wires going to it. (Bob's pic above is an A/C car, mine is not)
HornRelayLocationRed.jpg HornRelayRed.jpg
1) red wire is always on power
2) tan one goes back to the steering wheel. When the horn ring on the wheel is pressed, it grounds that wire, completing the circuit to the relay and energizes it.
3) Black wire hooks to the two horns. When the relay is energized, the red wire is connected inside the relay (via a magnet) to the black wire and power flows to the horns
To check the relay
1) Test there is power to the red wire. Disconnect it then use your multimeter and put the positive lead on the red wire's connector and the negative lead just touch to any bare metal. It should read 12+ volts. If not you need to trace that red/power wire to find the problem. On some '55s there's a Horn fuse in the fuse panel so check that first. On others it may share the 40amp circuit breaker with the power windows (behind the Driver Side kick panel).
2) Test the tan wire. Disconnect it and touch a wire lead to the connector on the relay and ground the other end/lead to bare metal to complete the circuit. The horns should sound as you're completing the circuit just as pushing the horn ring on the steering wheel would do. Your relay works.
3) Test the black wire: Touch the black and red wires together and the horns should sound. If not there is bad wiring from the relay to the horns that needs to be tracked down or the horns themselves are bad (they sometime stick after prolonged non-use) Power directly to the horn should make them sound
If test 1,2,3 above all test positive, your horns work, your relay works and the culprit is likely the tan wire that goes back to the steering wheel horn ring inside the steering column
There are a couple of threads that go through how to fix it at the steering column. You'll have to remove the steering wheel which means pushing down the emblem button on the steering wheel and turning it 'til it pops out to get to the nut that needs to be removed, then a steering wheel puller to get the wheel off (borrow for free at many auto parts stores).
Here are those threads. A more extensive search in the Technical section will bring up some more.
Here's the basics of how it works:
55 Horn Basics (https://forums.cadillaclasalle.club/index.php?topic=103185.0)
Here are a couple more technical threads
Horn 1955 cad DeVille (https://forums.cadillaclasalle.club/index.php?topic=171995.0)
Replacing horn wire on 1955 Series 62 (https://forums.cadillaclasalle.club/index.php?topic=173256.0)
HornWireLead_SteeringColumn.jpg
Many, many thanks Terry!
So often the simplest issues evade me.
Turns out when I eliminated the voltage regulator for a one wire alternator I cut out the horn relay as well
stupid mistake.
Again thanks
Al
Glad it was an easy solution. I can personally attest from my own experience that you're not the first to spend time trying to fix such a "forced error".