Busted top alternator connector! Whats it do?

[seraphiem]

My batt light has been flickering on and now on at a steady idle for the last couple of miles. Yes I know what it is thanks to my Voltmeter mounted in the A pillar.

Overcharging by a small amount. Like 15 volts. Well...while trying to pull the top connector off the non-ground pin literally pulled right out of the connector and crumbled!!! That connector is really stuck in it.

From what I understand this connector is simply for the dash battery light. This correct?

Anyone now if I can get a new connector to splice in or do I resort to a junk yard for this?

Thanks All.

 

[NJSHO]

Is the connector you are talking about a 2 wire rectangular with rounded edges? If it is, that is part of the feedback for the alternator to regulate voltage. If it is damaged, it is probably why you are over-voltaging. A pic of the connector would be helpful.

 

[seraphiem]

Thats exactly the connector. I didn't know if it was for the dash light or for regulation. I figured it needed cleaning as I was slightly overcharging. Tried to pull the connector out and with barely even disturbing it, it pulled right out. Plastic connector is really wedged in there though.

Guess I'll try to pull it out tonight again. Hope I have some connector or wire to work with in getting that lead back on.

 

[hawkeye18]

There's an I circuit and an A circuit that go to that top connector (this is all from memory). The I circuit is what drives the light - it's connected straight to the battery, which means both ends of the wire have vbatt at it... so if the alternator output goes below the battery voltage (12v), the battery will start pushing current through the light due to the voltage differential. i.e. light comes on.

But... if will also come on if the alternator is overcharging. The battery can only really accept ~14 volts, and if the alternator is putting more than that out, then the alternator will push current down the I circuit (remember, different voltages), and also turning the light on.

The A circuit is the internal regulator circuit. The Internal Voltage Regulator (IVR) cannot determine intrinsically the voltage it's putting out, which is why there's a wire going straight to the battery (through some fuses, of course) to tell the IVR what voltage it's putting out. If it sees less than 12 volts, it will increase output to make sure it's charging at around 13 volts, or at maximum capacity... whichever is more.

This means, if the A circuit is open (disconnected), the alternator will see that there is 0 volts at the battery (omg!) and pump out every last volt that it's good for in order to try to charge that completely dead battery. This is why you're seeing 15v (which is ridiculous) at your voltmeter, and this is why your light is turning on, because that I circuit is making intermittent contact and briefly turning the light on because the alt is at 15v and the battery's at 14.something.

So... in summation, yes, it's important that both those wires be connected! Most parts stores will have that connector. It might not be in stock, but they have it. RockAuto is also a good source for these plugs, and IIRC they're only like $3 or so. you will have to drill the old connector out (you could screw a woodscrew in there and pull it out with that), then reinsert the (hopefully) good wire ends into the new connector. If worse comes to worse, you could solder the wires directly onto the terminals.

The footnote: your alternator will not last long pumping out 15 volts all the time. This burns up the IVR in a real quick hurry, and I would start saving up for a new one... like right now. They're about $130 at advance auto (with a core charge tacked on) with a lifetime warranty.

Any more questions? lol... yes, I know I type a lot. 140WPM FTW!

 

[seraphiem]

Wow, thanks for that info. Makes perfect sense now.

I discovered why I was so confused. PO had his mechanic install a new alt and splice in a new pigtail too. The pigtail wires were blue and red and threw me completely off. Tracing the wiring back into the loom and I discover the yellow/white feedback or A lead is trashed. All right that explains something!

Finally get this connector off and both terminals on the alternator are BEYOND rusted and corroded! Kick butt. Well not really, but I found part of the problem.

Foolish me I never realized you can get pigtails for most connectors.
Sadly, the connector listed at Rock is http://www.smpcorp.com/wmimages.asp?file=S737.jpg&partnum=S-737

Which isn't correct for the SHO orientation of spade terminals. Ohh well...quick fix for now is just throwing on spade terminals until I find the proper pigtail or outfit the old one.

Thanks All.

 

[seraphiem]

Problem fixed! Just threw spade terminals directly onto the alt top connector to buy me time while I find the proper pigtail.

Gotta love these few rare easy fixes!

 

[hawkeye18]

yup, the connector is there just so you a) don't get them backwards and b) to (sometimes) seal out moisture, rain, dirt, etc.

 

[Storm-Chaser]

SMP (Standard Motor Products) has changed their website, as the product link below no longer works. The website is different from when I last visited, and there no longer are any product-direct search links or search boxes readily available until working well down into the website.

You can still get to their products pages, but now through a much more antiquated process. From the main webpage, under the section titled "Engine Management", select "Standard Brand" from the drop-down menu. This will take you to their "Standard Brand" website (why the name change?). Then click through the following hotlinks in the left column:

1. Catalog Info - (Product Info takes you to their Product Information Newsletter .pdf links)
   
   
   • Application Lookup
     
     
   • Part Number Look-up ***
     
     
   • Unit Parts Guide
     
     
   • Cross Reference
     
     
   • OE Interchange
     
     
   • Marine Catalog
     
     
   • W&C Accessory
     
     
   • Medium/HD Catalog
     
     
   • OExtra
     
     
2. Click the Part Number Look-up hotlink, enter the part number and click search.

It appears they've changed the website, so you can no longer directly link to their individual products. I wonder what happens if you block cookies from their new website. You can no longer right-click most of their images for direct product links either. Hmmm, . . . too much eBay traffic . . . ?

Wow, thanks for that info. Makes perfect sense now.

I discovered why I was so confused. PO had his mechanic install a new alt and splice in a new pigtail too. The pigtail wires were blue and red and threw me completely off. Tracing the wiring back into the loom and I discover the yellow/white feedback or A lead is trashed. All right that explains something!

Finally get this connector off and both terminals on the alternator are BEYOND rusted and corroded! Kick butt. Well not really, but I found part of the problem.

Foolish me I never realized you can get pigtails for most connectors.
Sadly, the connector listed at Rock is http://www.smpcorp.com/wmimages.asp?file=S737.jpg&partnum=S-737

Which isn't correct for the SHO orientation of spade terminals. Ohh well...quick fix for now is just throwing on spade terminals until I find the proper pigtail or outfit the old one.

Thanks All.