Topic: Wiring

Fred Hanks	-- 06-29-2013 @ 7:53 AM
	I can't find a diagram to see where the horn relay goes,I have a new harness and can't figure the horn wiring out, my Ford book does not show it.... any help???
Fred Hanks	-- 06-29-2013 @ 7:58 AM
	I have a '49 F1 v8 6 volt sys....
supereal	-- 06-29-2013 @ 11:08 AM
	Fred: The horn relay should be on the drivers side of the firewall. Follow the wiring from the horn(s) and from the button wire that comes from the bottom of the steering column. The Ford colors for the horns are yellow/green from the battery source, such as the starter solenoid, blue/yellow from the horn button to the relay, andyellow/black from the relay to the horn(s). The horns are grounded thru their mounts. If you have a problem, be sure that the horn brackets are, in fact, a good ground. Often, the color coding of a replacment wire loom is incorrect, and be a problem if a diagram wasn't furnished with the wiring.
49fordv8f4	-- 06-29-2013 @ 2:40 PM
	Fred, On my 1949 F4 the horn has two wires running to it, there is no relay on the firewall so it must be built into the horn. A #10 yellow wire with a green tracer runs from the hot side of the start solenoid to the horn and a #12 blue wire with a yellow tracer runs from the horn and comes out of the harness at the base of the steering gearbox were the horn button wire from the steering column plugs into it. The horns on the F2 and larger trucks that I have had were all wired this way. The horn looks the same as the earlier trucks. The F1 may have a separate relay on the firewall and will be wired as supereal posted. I hope this helps, Mark Poley
alanwoodieman	-- 06-29-2013 @ 5:58 PM
	are your horn(s) mounted on the hood?, my 51 is and the relay is mounted on the firewall pass side near the hood hinge
supereal	-- 06-29-2013 @ 7:24 PM
	If it doesn't have a relay, someone removed it. The current draw of horns is very high, and will make short work of the horn button unless there is a relay. I've never seen a relay inside the horn. My truck manuals show a relay, usually the three pole version.
Fred Hanks	-- 06-30-2013 @ 7:42 AM
	My '49 F-1 had no relay as someone had striped it b4 I found it...the horn should go behind the grille ? I jus bought a relay on E-Bay that I will mount on the fire wall. Now I need to know what is the correct wiring, There is one wire from the horn button that comes out the bottom of the gear box and I have to go from there.. Thanx !!!!
49fordv8f4	-- 06-30-2013 @ 10:50 AM
	Please don't take this as argumentative as it is not my intention. I rechecked the wiring on my 49 F4 and there is no provision for a horn relay. There are TWO terminals on the back of the horn. One wire comes directly from the horn button and the other wire from the hot side of the start solenoid. The wiring harness is original and unmodified. The 47 COE that I had was wired the same way. As best as I can tell from the service manuals and the 1928-1948 Ford parts book that I have the TWO wire horns ( passenger up to 38 or 39 standards and trucks up to at least 49) did not use a relay. The horns with ONE wire all used a relay, beginning with 38 or 39 deluxe models. The 51 F2 parts truck that I have does have a ONE wire horn mounted on the underside of the hood but the relay is missing The horn on my F4 is mounted in front of the radiator behind the grill. If your horn has the straight tapered projector about 8" long (not the seash*ll shape projector) and has terminals on the back for two wires the relay shouldn't be necessary. Mark Poley This message was edited by 49fordv8f4 on 6-30-13 @ 10:50 AM
Fred Hanks	-- 06-30-2013 @ 11:03 AM
	SOOOOO...In not knowing for sure what was there when new ,I am going to use a relay and a pair of Trumpet 6 volt horns, anyone see a problem there ????
Fred Hanks	-- 06-30-2013 @ 11:03 AM
	SOOOOO...In not knowing for sure what was there when new ,I am going to use a relay and a pair of Trumpet 6 volt horns, anyone see a problem there ????
supereal	-- 06-30-2013 @ 11:53 AM
	One fact with Fords is that often there are often differences that are not "universal", but my references show that the horn relay was added to trucks in 1948, and the six volt version, 7RA-13853, was then installed thru the 1955 model year. If a truck doesn't have a relay, it is probably not a "deluxe" model, and some standard models apparently didn't get one after 1947. If not, I'd install a relay, as they are less than $20, and will preserve that high current system.
49fordv8f4	-- 06-30-2013 @ 1:35 PM
	Fred, sounds like that should work. Run the wires as supereal mentioned in his first post and you should be good to go. Mark
49fordv8f4	-- 06-30-2013 @ 1:45 PM
	Supereal, I'm learning working on these old trucks that nothing is set in stone. I think the assembly plants utilized what parts that were on hand left over from older models. For instance my truck, an early 1949 assembled at Kansas City, has the same cowl to fender seal stapled to the flange of the fender as the 42-47 trucks instead of the foam seal normally used. So maybe the Kansas City plant had some older horns left over also? Mark
bonusbuilt1950	-- 06-30-2013 @ 3:53 PM
	I've parted probably 6-8 F-series from F-1's to a F-4 and I've only had relays on the 51-52's with the hood mounted horns. And it was mounted near the starter relay ( V8 ) None of the single horns in front of the radiator had relays. I have also found single wire horns and dual wire horns on 48-50's. THese all had factory wiring and not all hacked up. The 48-54 and 48-55 parts catalogs show a relay with a tan cover, but if you look at the wiring pic in the catalog, they don't show a relay in that pic until 1951. On page 276 of the shop manual it states " Deluxe trucks are equipped with a pair of tuned horns controlled by means of a relay" Now the deluxe series of trucks did not appear until 1951. THe accessory trumpet dual horn kits had a relay. I am inclined by what I've seen over the years and the various parts catalogs and the shop manual, that trucks with single horns (48-50 ) did not have a relay. 51 and up did. I did not consult my 48-56 series parts catalogs as they were first printed in 1964 and were sort of a compilation and final issue that year. They are riddled with lots of mistakes and omissions and are a joke. I did Ford parts for 30+ years and have run into tons of mistakes in catalogs. Ford finds thier mistakes in catalogs from the people at the dealer level. If you want to put a relay in, go ahead as it's added insurance, but if you're doing a 100 point resto, I say no. Barry 50 F-1
TomO	-- 07-01-2013 @ 7:58 AM
	Here is a link to the wiring diagram and schematic for your 49 pickup. It does not show a horn relay being used. http://www.vanpeltsales.com/FH_web/flathead_drawings_electrical.htm Tom
supereal	-- 07-01-2013 @ 4:14 PM
	I haven't seen a truck with two horns without a relay. The single horns usually had two wires, one to the battery source, and the other to the horn button, which provides ground. Horns draw heavy current, and two need the relay. Much Ford literature says car horn relays began in 1939, but I have seen them on earlier models. The '38 had them, but the '37 did not. In looking at wiring diagrams, I agree that one horn trucks did not have a relay. I stand corrected.
TomO	-- 07-02-2013 @ 7:40 AM
	One mistake in over 5,000 posts is a pretty good record. I wish that I was that accurate. Tom
supereal	-- 07-05-2013 @ 2:55 PM
	No, Tom. My mistakes are one heck of a lot higher than that. As frequent posters, you and I are certainly aware that trying to diagnose problems at a distance is usually a 50/50 proposition, at best. My dad used to say it was "like trying to judge a pig in a barrel". At our shop, we see plenty of jobs that perplexed others, including some dealers. Even with the OBD scans, some elude conventional diagnosis. We are headed to an era where vehicles will be plugged into a master computer back at the factory, and a list of repairs will emerge. The days of Gus Wilson and the Model Garage are long gone! Bob S.
TomO	-- 07-06-2013 @ 9:04 AM
	Bob, have you ever thought of what is going to happen to these vehicles as they approach 25 years? A neighbor had to scr*p a very nice 1993 Cadillac because the ECM was bad and the shop could not find one in the scr*p yard or find any one to repair it. My son had to hunt all over the US for the module that controls the climate control in his 1997 Mark VII. It took 3 months to find one. What is going to happen to all of these hybrids when the batteries die? Chrysler just recalled a bunch of cars because the computer module in the head rest may malfunction in a collision. Why they need a computer module in the head rest is beyond my comprehension. Tom
supereal	-- 07-06-2013 @ 3:57 PM
	Tom, nothing much surprises me regarding newer cars. The trend toward muiltiplexing to save wiring is a nightmare. Various components are linked by a common "bus", and are activated by digital command. Trying to diagnose these is bad enough, but many manufacturers have made the information "proprietary" requiring a fee to non dealers. We use ECM rebuilders for replacements, as the salvage yards around here don't have any. If the problem that killed the original ECM isn't found and fixed, the replacement will be turned into a paperweight as soon as it is plugged in. Chrysler has blamed the Japanese tsunami for the defective chips. They are used to position the headrest in the event the airbag system detects a crash. Frankly, I am not a Chrysler fan, as we see way too many of their vehicles in our shop. Our shop truck, an '07 Dodge, has already required replacement of most of the front end parts, including the wheel bearings. If Fiat doen't get their quality problems fixed, they are headed for big trouble. They are resisting the recall of the Jeeps because the gas tank mimics the same location that made the Ford Pinto a death trap. I think the answer to your question is that none of today's cars will be here, or fondly remembered in 25 years. Of course, that goes for many of us, as well!
TomO	-- 07-07-2013 @ 8:38 AM
	Back in the early 1980's, IBM adopted the serial bus for some of their products. It is a much less expensive way to handle communications between micro processors and it is less troublesome than multi connection cables. It was difficult to develop servicing procedures at first, but as they became more prevalent, it became easier. Today it is not a problem because the replaceable units contain so much circuitry and error detection methods, that the tech can easily find the failing unit and replace it. The problem of proprietary information on the bus and how to handle it is not an easy one to solve. If you allow a program in a test device to decode the bus information, you give your competitors a good look at how you designed the microprocessor. The current solution is a proprietary reader program that doe not disclose the actual buss content, but allows the user to see the result. I still don't see the need t have a micro-processor move the headrest when if they made it adjustable for the user, you would not need the motorized adjustment. Tom
supereal	-- 07-07-2013 @ 1:17 PM
	Tom, I have come to believe that the design engineers have turned their attention to creating "improvements" that make operation so complicated that ordinary things require undivided attention that threatens driving safety. When we took delivery of a new Lexus last year, even the dealer couldn't explain how to do the radio presets with the new system! A local dealer sent us a newer Cadillac that had an obvious problem with a dead battery. We found the cause was a failing R/C circuit that controlled the dimming of the interior lights. It was located inside the rear light, and was failing to turn completely off, but would drain the battery overnight. It didn't show on the wiring chart. Dealing with microvolts and microamps is a whole new ballgame, and doesn't bode well for car longevity. This message was edited by supereal on 7-7-13 @ 1:19 PM
TomO	-- 07-08-2013 @ 8:28 AM
	I agree completely. I had to get rid of my wife's 1998 Taurus, and shopped all of the new crossovers. I ended up getting a Chevy, because it had the simplest controls for the radio and other driver controls. She has had the car for about 2 months and still gets confused with the multifunction controls. The engineers are asked if you can do something and because of newer technology they can, so it is done. Then all of the unintended consequences show up when the vehicle is delivered to the customer. They use microprocessors for items that could be handled by a more simple approach, but is cheaper to do with the electronic already in place. You cannot buy a simple vehicle that can transport people comfortably today. The only simple ones are the econoboxes that you have to be a contortionist to get in and out of. Tom
supereal	-- 07-08-2013 @ 2:45 PM
	It isn't only cars. We bought a new GE kitchen range a couple of years ago, and my wife still hates it. In order to change the oven temperature, you must turn the oven off and start over, reprogramming it to the desired temperature. She (and I) don't understand why a simple knob wouldn't be much better! Just because exotic microprocessing circuitry is available, you don't HAVE to use it! I was a broadcast engineer for more than three decades, and saw technology "progress" from tubes to transistors, and on to integrated circuits (black boxes), making diagnosis and repair difficult to impossible. That was nature's signal for me to go home and play with my old cars!
TomO	-- 07-10-2013 @ 8:16 AM
	Amen. Tom
Fred Hanks	-- 07-11-2013 @ 7:21 AM
	Jus got horn relay 4 my '49...there is no marks as to what wire goes to where on the 3 posts ? I will pull power from starter sol. wire #1 ,wire #2 from bottom of steering box & #3 to horns...
supereal	-- 07-11-2013 @ 11:08 AM
	The three posts go to 1. battery, 2. horn button or ring, 3. horn(s). To identify those posts, place an ohmeter across the first two. If you get a reading, that is the relay coil. The horm post will show no connection to the other two, as it goes to the output of the relay points, and isn't powered until the relay is pulled. Most of the relays I've seen use the first post for battery, second for the button or ring, and the third to the horns. Many repro relays are not marked. If the horns don't blow at high output, reverse the battery and button connections at the relay.

EFV-8 Club Forum :	https://www.earlyfordv8.org/forum
Topic:	https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=17&Topic=6239