...Wiring Harness (LJ-TJ) 76-79 and the Diagnostic connector

[postman]

Dodge decided to discontinue the "incomplete chassis" for motorhomes as early as 1976.

Production in 1977 resulted in overstocked shelf inventory of 440-3 crate engines that were available maybe as late as 1981.

It appears the last m400 and m500 chassis were produced on Warren Truck assenbly line in 1979 when the specialty Sherwood assembly line was closed.

Thats the back story the way I inderstand it. Why does it matter? I am trying to determine the most accurate schematics. I have found conflicts and things that make no sense.

First, best I can tell the "Horn Relay Switch" was new to Winnebago in 1978. In 1979, Dodge/Winnebago chassis is produced with a diagnostic connector with no purpose, until Dodge discontinues the chassis in a year or two.

I am not going to purchase a half dozen manuals that have maybe a couple of pertinent bread crumbs in a collection of useless information each. Add to that what private revisions have been made. For example, my coach has no less than three sets of horns One a set apparently OEM (requiring a horn relay), and appears to be changed to 3rd party air horns. then retrofitted with horns not requiring a horn relay as I cant find one.

DaveVA78 have you happened across this? Does anyone relate to any of these issues in the timeline 1975 to 1980?

[/size]thanks

[DaveVA78Chieftain]

I have a hunch your are fighting:
1. What the original 75/76 Dodge design was.  2 horns with no horn relay with the horn ring being used to complete a ground circuit.
2.  What modifications Winnebago made.  Far as I know, that was to just add a horn relay.
3.  What a PO did.  Add or convert to air horns.

To me this comes down to what do you want the end result to be?  Then implement that design.  Don't blame Dodge for modifications Winnebago or a PO (or you) made to the original Dodge design.  While dodge implemented the center dash monitor panel (water level, tranny fluid level, etc.) around 1976, it was not covered in the service manual until 78/79.

The Diagnostic Connector was implemented in 1979.  As described in the 78-79 manual, along with pinout, it simply provides a central point for testing charging, starter, and ignition voltages.

[postman]

DaveVA78,


Do you have a horn relay? If so where is it located?


I have determined the are two different Fuse_box. The one I have, see picture. And one PN 3895458.





There appears to be a windshield wiper 2 speed relay mounted on the left of the housing, not in any schematic. A preferred outcome is a conversion to a Blade fuse box.


The rule of the day is measure twice, test twice, and consider exactly what you're about to do.  As for the horn relay the picture below demonstrates an alteration to convert a ground completion circuit to a positive current energizing circuit. Circled is what appears to be a resistor, but it is a poorly depicted magnetic coil reed switch.


Now what I need is a hint where its located.





The yellow line is the circuit to the horn button ground switch.


I prefer a fused horn relay.

[postman]

Made a little progress.


Found another set of horns OEM. I followed a string of the horn wiring up to the deck under the dash (driver's side) through a grommet.


Another project was to make sure the battery tray slides, strong enough for 3 batteries, and could be secured with a lock. I also wanted to be able to remove the tray to access the wiring and relays from directly underneath. All that was required was cutting a 3/4" by 3" +/- notch in the rail the tray slides on realative to the front. I added a 21" rubber bungee strap across the top of the bay to hold the battery cables out of the way off when closing the tray which was obvious had happened. Tomorrow I go hunting a horn relay if it exist.

[DaveVA78Chieftain]

Any aux relay will work (e.g fog light)

[postman]

Any aux relay will work (e.g fog light)

Dave I had a unique experience with a Chevy C-10 Hi-beam foot switch. Stepped on it once too many and a short damn near burned the truck up. The wiring had been altered I found as I took apart the melted harness.


Not doubting you, just cautious. Did Dodge have a part # for a 1978 horn relay?

[DaveVA78Chieftain]

Dodge 1791437
https://www.google.com/search?source=hp&ei=DyOGWqy_G66m_QbCu6GYCw&q=Dodge+1791437&oq=Dodge+1791437&gs_l=psy-ab.3...2444.24796.0.26595.15.13.1.1.1.0.330.1964.0j12j0j1.13.0....0...1c.1.64.psy-ab..0.12.1595...0j0i131k1j0i22i30k1j33i160k1.0.z8I5AYVGUKo

[postman]

 


Thank you