1970 Bug - Stereo Wiring

[combslv1970]

Hello, newbie here thank you for listening, I am looking for some help please.

I recently purchased a 1970 VW bug sedan.

Here is the problem; when I am driving and I have the Stereo on (Aftermarket stereo – Custom Autosound “Concourse Series USA-230) and when I use the left turn signal the stereo cuts out (no sound) and the light on the stereo blinks with the blinker. However the issue resolves it's self when I turn the left blinker off, the stereo goes back to sounding and working normally.

I have a 10 fuse - fuse block

The stereo's Yellow Wire (Battery - constant power, always ON regardless of the position of the key switch) is hooked up to fuse block in the number #2 (second row from the left / passenger side of the car), see Photo #1.

The stereo's Red Wire (Ignition - Switched OFF when the key is in the OFF position) is attached (via a yellow plastic coupler), see Photo #2 and Photo #3 up to a black/white wire that come off a TR Top Relay TRP 412.400 – 49a (I believe). According to my research I think this wire (49a) is the Emergency Switch & Turn Switch.

Is there an easy fix to this? Seems like the problem is the Red Wire (Ignition - Switched OFF when the key is in the OFF position) correct?

Thank you.

[VW_Jimbo]

That wire going to the relay is the pulsating voltage for your directionals.

That wire should be removed and the damages repaired there. Then connect that wire to the fuse at the other end of the fuse panel. It should have black feed wires on the high side of the panel and black on the low side, except for one light green one. Either the last one or the next to last one may work.

Please take a test light or volt meter to confirm ignition power with Key on engine off in the run position.
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Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[Vanillagurilla]

Haha I can't believe someone would pull power for the radio from a wire attached to a relay. Crazyness.

[VW_Jimbo]

I have seen way crazier things! Had someone utilize an O2 sensor signal wire for an alarm system. Rolled into my shop with an O2 low voltage code and running like crap! I have seen quit a bit of crazy wiring issues. Good times!
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Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[gt1953]

Wow that is a cool prank to pull on someone.
On the over all condition of the connections. Clean them up as they appear to be corroded after all of these years. Ok how do I do that. Obtain a dremel tool. Use the small wire wheel, one at a time remove each connector, use the dremel wire wheel to make them shiny. Also remove the fuses, make the connections that the fuse contacts shiny, then on every ground connection.
If you do decide to improve the current flow by the above procedure disconnect the battery first.
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Volkswagen: We tune what we drive.
Numbers Matching VW's are getting harder to find. Source out the most Stock vehicle and keep that way. You will be glad you did.

72 type 1
72 Squareback
({59 Euro bug, 62, 63, 67, 68, 69, 73 type ones 68 & 69 type two, 68 Ghia all sold})

[bluebus86]

from the photos, you have some fairly dirty corroded connections on the fuse panel. disconnect your battery before working on them, remove the connectors (mark them or take great photos first for reference) and get that cleaned up, shiny brass is what you want, do likewise on the fuse connections, and replace old fuses as the ends get corroded too. you may find everything works better, brighter, and happier with all that near 0.4 century old grim and corrosion cleaned up
Do likewise on the switch connectors, key switch, headlight switch, etc...

And after that address a major fire risk on your fuel system, see link at bottom of this post for engine fires and safety wires.

Good Luck, Bug On with a Great Electrical System! Only You Can Prevent Voltage Drops so says a Bavarian Bear!
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Help Prevent VW Engine Fires, see this link.....Engine safety wire information

Stop introducing dirt into your oil when adjusting valves ... https://www.thesamba.com/vw/forum/viewtopic.php?t=683022

[Cusser]

Yes, red power wire is connected to wrong location - at the flasher relay - and uses a connector I don't like. Amazing the Doofus-like wiring we find on these old VWs, guy who installed that likely thought he knew what he was doing !!!

If you have a yellow "memory" wire, that should be connected to fuse box location like for dome light, which is always powered.

Connect to a "switched" fuse location on the fuse block, get a dual-male connector from the parts store if you need that.

I also see a home-wiring wire nut in that photo, ridiculous !
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[combslv1970]

Thank you for all your help, here is an update.

I came the realization that you can't do this job correctly with out a test light, down to the auto store I went.

After testing all tabs on the fuse block panel (under the front deck lid) with the Key ON and Key OFF I found that the only tab that always has power with the key not in the ignition is TAB #1 (far left side of the fuse panel / passengers side). I relocated the stereo yellow wire (battery / memory wire) to Tab #1.

Then I disconnected the red wire (Ignition Wire) from the flasher wire, as you guys suggested (thank you) and repaired the huge gash the clip left, then I moved the red wire to TAB #10 (far right side of the fuse panel / drivers side). This tab available on the fuse block and tested off (no power) when the key was not in the ignition.

The wife and I took the car for a spin, turned on the stereo and then turn signal and PRESTO problem fixed, no more stereo cutting in and out!!

Please feel free to let me know if I missed something and/or did something wrong - Stereo works.... Just don't want to screw something up with a parasitic drain to the battery.

Thank you again for all your help - enjoy the photo!!

[Cusser]

[VW_Jimbo]

That’s great. Sounds like you got it! Enjoy driving with the new tunes!
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Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[ashman40]

Just wanted to give some feedback...

[combslv1970]

Thank you for the follow-up and again thank you to everyone for the support and suggestions, this form and the members are a wealth of knowledge beyond belief.

I just want to make 100% sure I am doing this correctly, in my handwritten diagram is the “Current” position of the stereo’s YELLOW WIRE (Battery/Memory – always ON regardless of the position of the key) and the stereo’s RED WIRE (Ignition Wire – Switched OFF when the key is in the off position).

The suggestion is as follows;
move the yellow wire (Currently in Tab 10) and the red wire (Currently in Tab 1) from the output bottom row closest to the bumper (Fuse Protected side) to the input top row closest to the dash board (Fuse Unprotected Side).

You are correct, both of the stereo wires (Yellow and Red) have inline fuse holders.

Here are current pictures of the wires on the fuse block since my last picture post.

The gunk on the current fuse block is the light over spray from the paint job (VW Gemini Blue Metallic L96E) which I will get cleaned off with the dremel and the wire wheel. As soon as I get the stereo issue resolved.

Thanks again guys!!

[Cusser]

Per your question you COULD move the red and yellow wires to the UN-FUSED side of the fuse box because they have their own inline fuses, but there's really no advantage in doing this.

My own yellow and red wires do have in-line fuses, and are on the FUSED side of the fuse box. I've never burnt out any of those fuses or inline fuses either.

The inline fuses are quite small amp ratings, and if something shorted at the stereo, those inline fuses would burn out before the 8-amp fuses in the fuse boxes would.
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[Luft kühl]

[ashman40]

[Cusser]

[combslv1970]

Thank you again for all your posts!! Great news, the stereo works perfect and for that I am very appreciative!! I am considering getting a new fuse block instead of trying to clean the existing one and go from there!! You guys are the best!! Fahrvergnügen on!!

[Cusser]

[combslv1970]

Thank you Cusser, I have always been a big fan of your previous posts / reply's on other topics. I just had total hip surgery and cleaning the fuse block is number one on my list to do once I am back on my feet....