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Discussion Starter #1
If anyone is having a low voltage issue in their gtv6, I may have the solution for you. I have been diagnosing slow windows and slow wipers on my son's gtv6, and have found an interesting cause.
First, this applies to an 82 gtv6. Later cars may not have this issue. When checking the voltage at the fusebox, I found that the fuses that are energized when the ignition is switched on, had a voltage drop of over 2 volts. If the battery voltage was 12.6v, the voltage at the output of fuse #6 was only 10.5. That is substantial! No wonder the wipers and the windows creeped along so slowly.
Now the cause. I traced every circuit that is energized from the ignition switch and found that only one caused this voltage drop. It was the bosch ignition module located near the coil on the front driver's side inner fender. Once I unplugged this unit, the voltage output was back to 12.6 at the fusebox.
The solution? Install a relay. Splice the green/black wire that powers the unit from the ignition switch into a relay. get power from the alternator junction block just above the unit and feed it through the relay to the Bosch ignition box.
The result: wipers and windows now operate at a reasonable speed, gauges no longer lag at idle, and the battery light no longer stays on at any rpm over idle.
If anyone is interested, I can snap some photos of the relay system I installed under the hood and add them here.
Thanks for reading and keep those v6's going!
 

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Now THAT is new information, as far as I know. I never recall seeing that specific culprit posted here on the BB, unless I just missed it (possible...).
You got my curiosity up big-time... I'm going to check it out. We already have an ignition relay on the car at the switch. Molto grazie!!!
 

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I've heard that relays can also help solve the not-so-bright GTV6 headlights. Window motors and wipers as well. If you upgrade to more powerful headlights, I'm told you risk frying the column switch pack if you don't include relays. Just repeating hearsay... I'm no wizard when it comes to electronics. Will need to find someone better than I to make those upgrades.
 

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1986 Alfa Romeo GTV6
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Interesting.
I just started a post that i think is related.
And you actually may have found the cause.
This is great. when can i take my car over, lol. i hate (scared) doing electrical car fixes.
Post Pics, please,please, please.
 

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I've heard that relays can also help solve the not-so-bright GTV6 headlights. Window motors and wipers as well. If you upgrade to more powerful headlights, I'm told you risk frying the column switch pack if you don't include relays. Just repeating hearsay... I'm no wizard when it comes to electronics. Will need to find someone better than I to make those upgrades.
The relais is also a common fix to save the 105 giulia column light switches.
 

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The question is why? Is a relais the solution to the cause or just curing the symptom of??
Bad earth? Bad electrical components? Bad wires?
 

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The question is why? Is a relais the solution to the cause or just curing the symptom of??
Bad earth? Bad electrical components? Bad wires?
It looks like we may find out soon. After all, he found this localized to the Bosch ignition module, right? It could be corroded connections, dirty ground of the unit, or maybe something internal to the module as it ages. The bottom line is voltage drop has been localized, and a relay seems to fix the loss within dependent circuits. That's good enough for me. Besides installing a relay, be sure I am going to clean the connections to the Bosch module and the grounding screws, also.
I'm excited!
 

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WD40 or whatever lubricant you like the felt sliders, or whatever that fuzzy crap is in front and back of the window track.No modifications required. They are old and dirty causing the window to jam. Do this and they'll fly. I do this and recommended this many times. I don't have this issue and own 2 GTV-6's. My windows fly!
 

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Also install relays for the light switch. It's very easy. Have it on all my cars, some integrated in the fuse box some just hanging behind the fuse box. Having ~ 15 amp passing through a column switch is not good. Wish I could post that schematic? Takes a half hour. As far as the wipers they go faster at low speed than high, but this issue doesn't bother me. I can see through the rain. If someone can recommend a schematic source I will post it. The relay circuit.
 

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Discussion Starter #12
Here is a photo that I doctored with some writing to explain the relay setup. When I installed the relay, I opened the wiring loom from the bosch ignition box to the area of the photo. This exposed the green/black wire that leads from the fusebox to the ignition box (the one that powers it up when the ignition is turned on). I cut the wire and proceeded to install the relay. I believe the photo explains it from here.


1626780
 

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This is awesome! As @iabonip mentions, this is on an '82 and may not apply to later models. I think in '84 GTV6s moved away from the Bosch ignition box to an ignition module on the side of the disti (that's what my '85 has). So great news for you early GTV6 owners!
 

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If you check the factory wiring diagram, you will find that you achieved much of what is gained by installing the relay at the Terminal 15/brown wire from the ignition switch; the green/black wire to the ignition control module is just downstream of this point at the fuse box.

So, for those of use who have already installed the "standard" Alfa ignition switch relays, this is not breaking news.

@iabonip not trying to piss in your corn flakes, great find, but just trying to prevent people from hacking into their wiring again!

But if you haven't done so, a relay for each terminal of the ignition switch makes a world of difference on older cars like this.
 

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If you check the factory wiring diagram, you will find that you achieved much of what is gained by installing the relay at the Terminal 15/brown wire from the ignition switch; the green/black wire to the ignition control module is just downstream of this point at the fuse box.

So, those of use who have already installed the "standard" Alfa ignition switch relays, this is not breaking news.

@iabonip not trying to piss in your corn flakes, great find, but just trying to prevent people from hacking into their wiring again!

But if you haven't done so, a relay for each terminal of the ignition switch makes a world of difference on older cars like this.
You mean each fuse terminal that gets power via the ignition switch?
 

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You guys talk about this like it is common sense. lololol. I think i can read chinese better than this. Ups, can't say chinese these days.
 

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Yeah, the '84 - on cars have some wiring differences and apparently there are no factory wiring diagrams for them! I installed the IAP headlight relay kit and it really works well and should allow the headlight switch to live a little longer, since the full current draw isn't running through it anymore.

I was thinking about adding relays to the headlight and window circuits, but figured I'd have to trace stuff from the ignition switch, so I went back to watching Law & Order reruns. At the very least, this looks like a good place to start playing with wires!

Thanks!
 
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