2 4 0 T U R B O . C O M
D A V E ' S   V O L V O   P A G E
Cadillac 4-Note Horns
for my Volvo 240


     UPDATED: August 20, 2021                       CONTACT       
D  O  M  A  I  N  S
davebarton.com PrancingMoose.com 240Turbo.com
Payments and Policies
New Items
Cool Volvo Products 240 Modes & Fixes
Volvo
                  Stickers Volvo
                  SteeringWheel Labels
Volvo Wire Harnesses Volvo Harness Parts, Terminals, Connectors.
Volvo Prancing Moose Stickers Other Car Stickers Volvo Relays and Sensors. Volvo 960 coil harness repairs.
Volvo Underhood, Body and Chassis Sticker and
                  Labels Other Car Stickers 740, 760, 780 Turbo Boost Faces Volvo Custom Black or White Faces.
240 Black Door Vinyl Stripes. Volvo 240 Window Scrapers 740, 940 odometer repair gears and instructions. Volvo 240 Odometer Repair Gears and Instructions.
Wheel Center Cap Overlays. Volvo Group A Racing Articles Prancing Moose, Volvo R-SPORT Horn Buttons, replica Alpina horn buttons 240 Hydraulic
                  Clutch Volvo Adjustable Voltage Regulators
Volvo Meet Photos. Electric Fan Diagrams Volvo
                  tropical fan clutches SoCal Area Salvage Yards Side Markers on 240s and 740s Modified 240s
Unleaded Race Fuel at the
                  PUMP
B26FT Stroker
                  Build
Volvo
                  Vacuum Diagrams
Dave's 245
                  Specs Used Volvo Stuff 240 big brakes
R-Sport
                  apparel from Cafe Press
Prancing Moose Apparel from Cafe
                  Press 240 Suspension Mods Favorite Links

Send me an email if you do something like this to YOUR Volvo.
CONTACT
https://www.youtube.com/watch?v=ygKKAqmxLS0


This is what stock Volvo 240 horns look like. 
They are mounted behind the grill. 
My original horns sounded ok.  Nothing special though. I wanted SPECIAL!.

Here's my 1984 horns.


Here are what late 240 horns look like. This one is from 1993.



I had been thinking about doing a LOUD HORN upgrade for a while and I finally pulled the trigger.  I found a set of these four (4-note) horns online and bought them. 

These are known as Cadillac 4-Note Horns. I don't know the specific years, but these horns were equipped in many Cadillacs up into the 1990s. Specifically they appear to be found in Cadillac DeVilles until about 1985 (after which the Deville was downsized). They also came in Cadillac Fleetwoods and large Buicks until about 1995. Also supposedly in Oldsmobile Toronados until about 1985.
 
These horns are made of steel and plastic. Much earlier Cadillacs and large GMs got 4-note horns going back into the 1950s. Those much earlier horns were all metal and may have very different markings.

The four horns below are each tuned to a separate specific note: A, C, D and F.
Later cars with only 2 horns reportedly got only notes A and F. 
After the 4-note horns were discontinued, all GM cars came equipped with only two horns.


NOTE ABOUT BUYING THESE HORNS ONLINE
There are eBay sellers who offer Cadillac horn sets like this. Most of them claim to have tested them before sending to you and I think most of the sellers are probably reputable.
But shop carefully.


 Be aware that these horns are pretty old and it's reasonable that there could be a little corrosion (rust) on the inside.  If there is excessive corrosion, they will sound poorly or stop working completely. 
TEST THEM YOURSELF with a battery after you get them, ONE at a time. 
I have bought a few sets. One set I bought as a gift from an eBay seller was reportedly tested by the seller. I could not test them myself, because I had them sent directly to a relative, who didn't test them before spending good money to have a shop install them (and of course the professional installer also failed to test them individually).  The horns sounded bad and after an investigation it turned out we got BAD horns. Two of them produced a muffled sound and one had no sound at all).
This means ONLY ONE HORN WAS WORKING CORRECTLY.
When I contacted the seller he REFUSED to accept a return until I filed and won a Paypal dispute.


I don't really suggest disassembling these horns, but here's a video below where someone did this and it shows what a LOT of corrosion will look like. This person was able to restore the horns and make them work again.
https://www.youtube.com/watch?v=L1kMJIKSEQc

And here's a very detailed video on how the internal diaphragm makes sound.

https://www.youtube.com/watch?v=zHyvKkNLf0Y


  
The round portion of these horns is stamped steel and the trumpet section is molded plastic.

Each horn has the note A, C, D or F embossed as shown here.
 

 
The horns I found have two-wire connectors (power and ground). These are reportedly later model 4-note horns. When shopping for horns, be aware that there are some (see lower photo) which have only ONE wire to each horn. 
That wire is the power wire.  These are reportedly earlier horns. On the ONE-wire horns the ground circuit is completed through the mounting bracket.  I don't think this makes any difference in how they sound.  Just be aware of it in case you have a preference.

If you're installing these in a Volvo 240, you should know these cars don't have normal horn activation circuits.  The 240 has YELLOW and BLACK wires as shown here. The yellow wire is the power wire and it has 12 volts whenever the key is in the ON #1 or ON #2 position.  The horn is then activated through the black GROUND wire, which is triggered by the horn button on the steering wheel.

The Volvo 240 does NOT use a relay in the horn circuit.  In order to make these 4-note horns work correctly, a relay is being added below to change how the new horns are powered and triggered. 

If you're installing these horns in a non-Volvo with a normal horn circuit, I would still advise installing a relay to provide power.  These horns reportedly draw about 5 amps each and I think they'll always work better when direct full battery voltage is available.


WIRING DIAGRAM
Here's a diagram I made. This is how I made my relay circuit. 
I used TWO relays. Each relay powers two horns. I suspect that ONE relay is probably enough for all four horns, but I did it this way after seeing the majority of other installations doing it this way.

Keep in mind that Volvo 240 horn circuits are different from most normal cars.  The horn switch on the steering wheel in a 240 is a ground circuit, instead of a 12V power circuit like a normal car. So if you have a 240, look for the two-wire harness going to your horns and you'll find the yellow and black wires shown below.


I carefully straightened the mounting brackets on all four horns using my bench vise and big pliers.  I also ended up cutting about an inch off the end of each bracket.  That's up to you on if this helps you mount them.

I've heard it may be possible to mount these so they're too stiff or too rigid.  I don't know if that's true, but certainly mounting them so they can't freely vibrate can negatively affect the sound. Keep this in mind if you're cutting down the brackets. These horns vibrate a lot when sounding, so you should mount them so they are not touching each other or touching any other parts of the car (except of course where the brackets are mounted).
 
When mounting these, keep in mind that the trumpet openings should be pointed downward so they don't collect water.  Also I have read that the best sound will be from horns that all are mounted close together and, if possible, all pointing the same general direction. 



Here's a photo ABOVE of the horns installed behind the front grill in my 240. After I was done, I changed my mind because this location really sucks.

 I didn't like how much air these blocked going to my AC condenser and radiator and I didn't like how they were all pointing different directions. 
So instead I and mounted them BELOW the car.


SEE PHOTO BELOW.
A 240 has lots of room underneath in the right or left corner, behind the front bumper.
I mounted these under the left side. The horn brackets mounted below are actually mounted to the 240 horizontal support bracket that stabilizes the left fender. It's a TIGHT fit in this space next to the charcoal canister. They just barely fit on this side, but they do fit and none of them are rubbing or touching each other or any other parts of the car. That's important because of how much VIBRATION these things generate. 

You might also consider mounting them on the RIGHT (passenger) side, since there's more room. There's no charcoal canister over there. I didn't choose that side because I already had a remote oil filter mounted there.  This gives you two great locations to choose from, and I think they're louder in this lower position, since all of the trumpet openings are pointed downward to FREE AIR instead of being pointed at parts of the car. 

It's hard to tell from this photo, but the lowest part of the horns is well above the bottom of the spoiler and they're not visible unless you get on the ground a peek under the car.

Below photo view is from the ground looking up.


MOUNTING DIAGRAM
Here's a diagram below I created to illustrate how I mounted these horns. I bent the horn brackets to point the horns a bit forward, moving them away from that charcoal canister. And then I bolted together each pair of brackets above the 240 fender brace so that the brackets sandwiched the brace. I did this because I felt drilling holes in the brace limited my options for small adjustments in the final positioning and my goal was to get these things positioned just right so none of the horns would be rubbing or touching or vibrating against anything.


If you're wondering what hole I used to bolt these brackets together in the above diagram, it's this one circled. 
Send me an email if you do something like this to YOUR Volvo.
CONTACT
 


davebarton.com
prancingmoose.com
240turbo.com
Contact Us
Prancing Moose Stickers
Volvo Stickers
Body/Chassis/Engine Labels
New Items
Other Car Brand Stickers
Steering Wheel Labels
Center Cap Labels/Overlays
Cool Volvo Products
Grill Labels/Overlays
Volvo Wire Harnesses
Conversion Harnesses
Harness Parts/Connectors
Volvo Relays
Coil Repair Harnesses
240 Window Scrapers
740/940 Window Scrapers
Adjustable Voltage Regulators
Horn Buttons
240 Odometer Repair
740 Odometer Repair
Volvo Gauge Faces
740 Turbo/Boost Faces
240 Black Door Vinyl
850 Odometer Repair
240 Alternator Mod Page
240 Power Mirrors- Switches
240 VIN Decoding
240 Fuse Panel Page
Group A Racing Volvo 242 Turbo
240 Lowering Page
Fuel Pump Relay Mods
240 Headlight Relay Page
Used Parts & Stuff
Harness Crimping Page
240 Ignition Page
Classic Auto Air AC
240 Gauge and Electrical Diagrams Limited Slip Read Ends Yoshifab Catch Can Install 240 Mods and Fixes
Side Marker Lights Gentex Mirror Upgrade Yoshifab Drain Tube Install Modified 240 Favorites
SoCal Salvage Yards Unleaded Racing Fuel B26FT Stroker Dave's 245 Spec Page
240 Suspensions 240 Hydraulic Clutch
Vacuum Diagrams Volvo Meet Photo Albums
240 Big Brakes 240 Dash Top Gauge Pod Cadillac 4-Note Horn Install 240 Dynamat Install
4 Speed Fan Controller
Electric Fan Diagrams
Tropical Fan Clutches
Favorite Links
Volvo VIN Decoding Page 240 Oil Cooler Page
Stepper Idle Valve Page
240 Windshield Page
R-Sport Apparel
Prancing Moose Apparel
Mojave Road Trail Page
Texas Volvo Meets and Events
Ordering Instructions Policies Payments Shopping Cart Troubleshooting
Returns Shipping


Online Payments