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DPDT Relay Issues

Discussion in '308/328' started by 1Evil4re, Aug 31, 2013.

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  1. 1Evil4re

    1Evil4re Formula Junior

    Jun 24, 2012
    313
    Nashville Area
    Full Name:
    David
    #1 1Evil4re, Aug 31, 2013
    Last edited by a moderator: Sep 7, 2017
    The previous owner used an automatic antenna that by-passed the aerial switch. It would come up on its own as soon as you turned on the ignition switch regardless if the radio was on or not.

    I purchased a Harada MQ1 and built my DPDT relay as instructed. As I was dry fitting everything before soldering my connections, the antenna went up on its own without using the aerial switch. I checked voltage on the wires coming from the switch and I had 12V on the red wire/spotted wire (circled) even when the ignition was off. I also showed 12V on the green wire/spotted wire when I turned on the ignition. This really doesn't seem correct.

    So I need some help from the electrical experts out there.
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  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,825
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #2 Steve Magnusson, Aug 31, 2013
    Last edited: Aug 31, 2013
    You need to check if you have the stock aerial switch in the center console and/or any wiring changes have been made in the center console (my guess is that you don't have the stock aerial switch and other wiring changes have been made based on your description). The way the stock switch works is:

    1. The H (grey) wire is always +12V and is connected to the center pole of the stock switch. When the switch lever is in the center (off) position, the H wire is not connected to any other wire.

    2. When you move (and hold) the switch lever one way, it connects the H wire to one of the BR (white-red) wires.

    3. When you move (and hold) the switch lever the other way, it connects the H wire to the other BR (white-red) wire.

    You must have a switch (and wiring) that works this way to use that DPDT relay modification.
     
  3. 1Evil4re

    1Evil4re Formula Junior

    Jun 24, 2012
    313
    Nashville Area
    Full Name:
    David
    #3 1Evil4re, Aug 31, 2013
    I do have the stock switch. I looked at it the other day including from the back. My blinkers stopped working so I took out the flasher switch and cleaned it. Didn't solve the blinker problem. While I was in there I looked at the aerial switch and it had the two red/white wires coming into and out of the switch. It doesn't have the grey H wire so it looks like the previous owner tapped into the harness some where along the way.

    Thanks Steve. You are always a wealth of information.
     
  4. 1Evil4re

    1Evil4re Formula Junior

    Jun 24, 2012
    313
    Nashville Area
    Full Name:
    David
    #4 1Evil4re, Aug 31, 2013
    Last edited by a moderator: Sep 7, 2017
    I just double checked my switch. I was wrong. As you can see from the photo, the grey H wire is still connected. The previous owner pulled off one of the red/white wires and used the in-line tap to draw power from the A/C switch. What an idiot!
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  5. 1Evil4re

    1Evil4re Formula Junior

    Jun 24, 2012
    313
    Nashville Area
    Full Name:
    David
    #5 1Evil4re, Aug 31, 2013
    Now does that wire plug onto the blade beside the other red and white wire or on the blade right next to the grey wire?
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,825
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #6 Steve Magnusson, Aug 31, 2013
    Just use your voltmeter or ohmmeter to figure it out (I wouldn't trust that the wires that are still connected are in the right places).
     
  7. 1Evil4re

    1Evil4re Formula Junior

    Jun 24, 2012
    313
    Nashville Area
    Full Name:
    David
    #7 1Evil4re, Aug 31, 2013
    Last edited by a moderator: Sep 7, 2017
    OK. I got the switch out and using a jumper between the grey "H" wire and the two red/white wires, I have the antenna going up and down. So my DPDT is assembled correctly and once again Steve was right as the wires as they were positioned on the switch were not correct. However, I am not smart enough with a multimeter to figure out where the three wires go on the 4 potential blades of the switch. Any help would be appreciated.
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  8. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,825
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #8 Steve Magnusson, Aug 31, 2013
    Just arbitrarily label each male tab with a name -- e.g, 1, 2, 3, and 4. Then measure the resistance between each pair of tabs for each position of the handle (don't worry about getting an exact Ohm reading -- it will either be 0 Ohms (connected) or infinite Ohms (not connected):

    Handle in center position
    1-2 =
    1-3 =
    1-4 =
    2-3 =
    2-4 =
    3-4 =

    Handle pushed one way
    1-2 =
    1-3 =
    1-4 =
    2-3 =
    2-4 =
    3-4 =

    Handle pushed the other way
    1-2 =
    1-3 =
    1-4 =
    2-3 =
    2-4 =
    3-4 =

    If you can fill in these results, we can deduce where to put the wires.
     

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