Diode in parking brake switch
Thread Starter
Instructor
Joined: May 2005
Posts: 114
Likes: 0
From: Gold Coast Qld
Diode in parking brake switch
I recently gutted the interior of my 73 vert to insulate and tidy up all the non working bits and pieces. I found a diode as part of the wiring that goes to the parking brake switch and have no idea why it should be there. My knowledge of electronics is limited but I have only ever seen diodes (which only transmit current in one direction) be used in AC (alternating current) situations.
Can anyone throw some light on the subject please.
Jeremy.
Can anyone throw some light on the subject please.
Jeremy.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
I recently gutted the interior of my 73 vert to insulate and tidy up all the non working bits and pieces. I found a diode as part of the wiring that goes to the parking brake switch and have no idea why it should be there. My knowledge of electronics is limited but I have only ever seen diodes (which only transmit current in one direction) be used in AC (alternating current) situations.
Can anyone throw some light on the subject please.
Jeremy.
Can anyone throw some light on the subject please.
Jeremy.
If it IS a diode, it's probably there to prevent "back voltage" - sending power to devices that should be off because the ignition is off. That's a strange application, though, because I don;t believe that circuit has voltage when the key is off. Hmmmmmm.
FYI, another use of a diode - specifically a Zener, is to limit the voltage passed through the circuit.
The configuration you mention (AC Circuit...) would be for rectification - turning an alternating (AC) signal into a Voltage (DC).
These are VERY simplistic explanations for clarity.
Racer
Joined: Oct 2006
Posts: 290
Likes: 30
From: Perth Western Australia
I think the function of the diode is to steer current away from the seatbelt warning buzzer when the key is in the ignition and the safety belt is unfastened. To do this you have to pull the handbrake lever up. So when you are working on the car the seatbelt buzzer does not sound and drive you mad.
I think this is the function from memory and 72 was the first year to use it. Try it and see what happens…
I think this is the function from memory and 72 was the first year to use it. Try it and see what happens…
