[WANTED] Park Brake Indicator Switch (1973 Duster 340)

[bd2595]

I have a 1973 Duster 340 I bought about a month ago. The main mechanical and paint issues are done, but there are a LOT of minor things that need to be fixed as well. The switch that activates the brake light when the parking brake is on is in pretty bad shape. There is a black wire that runs from the diode to the actual switch and then a black wire that runs from the other end of the diode to splice in close to the "brake" fail wiring. The black wire from the switch connects to a very small connector at one end of the diode and it is broken. I am going to try to carefully drill out the remaining wire and gently open the connector so I can get the black wires in at both ends. I would like to find another is anyone has one.

 

[Dana67Dart]

How about some photos.

Not saying it is not but I have not seen diodes on our cars, granted im not into 70 up so who knows.

 

[Dana67Dart]

The switch that activates the brake light when the parking brake is on is in pretty bad shape

I'm my experience the parking brake switch is basically a door dome light switch. It makes a ground when the handle is pulled out.

And is in parallel to the brake warning switch in the distro block that also makes a ground when one system ( front or rear) looses pressure.

It is a pretty simple system.

 

[bd2595]

I will need to post some decent pictures when I get home. I have the manual for 1973 and it's in the wiring diagram as well. The previous owner labeled it, they had removed everything, as the parking brake light and the wiring matches what is in the manual. I posted some pictures last night in a post but it was in the wrong room and it was deleted.

 

[Dana67Dart]

73 wiring diagram confirms

Low brake switch goes to M
M goes to printed cir board 10 and the parking brake switch
10 goes to one side of the light bulb
The other side of the lightbulb gets power from a switched feed

Wiring diagram available from mymopar.com

 

[bd2595]

I will send pictures from my manual. The switch goes into a diode (matching what I physically have) then the other end of the diode has a black wire that goes into a splice that does to brake lamp and low brake fluid/brake failure warning indicator.

 

[townsend]

The diode that bd2595 refers to was only used on 73-75 abodies with manual transmissions.

 

[Dana67Dart]

This is what the Parking brake switch should look like and has been used from 63-77 on basically all Chrysler cars

Is the terminal that plugs into the end of the switch

 

[Dana67Dart]

The diode that bd2595 refers to was only used on 73-76 abodies with manual transmissions

What is its purpose?

 

[bd2595]

Generally a diode ensures that power flows only in one direction so in this case towards the brake lamp to turn it on when the parking brake is on.

 

[bd2595]

Here are the pictures. The black wire from the actual switch was attached (barely with one strand) to one side of the end of the diode. The other end of the diode had no wire, but you can see there was a wire on it at one time. I am going to try to reattach as I said and finding another would be great.

 

[Dana67Dart]

Where does B3 go, it looks like it prevents a back feed from B3 thru the bulb to the bulbs feed.



From your photos I don't see any reason why you could not cut the broken ends off and crimp new proper ends on.

 

[townsend]

Go to mymopar 1973 Dodge chassis service manual - page 8-155.

 

[Dana67Dart]

Got it, that makes sence now.