Chevyboy454010

ok i had a voltage issue replaced everything installed the truck alt and replaced all battery cables as well as checked all of my grounds prior to the install of the alt. the issue im having now is my exciter has a short near the pcm connector. any advice on how to correct it would be appreciated. ive narrowed the short down to a specific area in the pic where its curved between the blue wires.

1. should i replace the entire wire all the way to the pigtail. also i have no idea how to remove the grey cover. how to do that would be helpful.

2. just cut out the bad area and solder in a new piece etc.

LS6427

iTrader: (2)

Just unscrew those two bolts, then as the bolts loosen you can wiggle the grey tops off little by little. The screws will come out and then free spin, when they free spin that's all they will come out....then pop the tops off.

I say replace the whole wire while you're in there, unless its a clean splice, then you won't have to run the wire all the way over there.

I you need a new pigtail/plug for the alternator, they are like $12.00 on eBay. Just search "LS1 alternator" and you will find it.

Here it is.....
http://www.ebay.com/itm/Camaro-Firebird-98-02-LS1-Alternator-Connector-Pigtail-/310659233558?pt=Motors_Car_Truck_Parts_Accessories&hash=item4854bbb716&vxp=mtr
.

Chevyboy454010

Ok thank you the pigtail was replaced recently its soldered in and reading good. I'll do what you said I rather not run a new wire all the way over there

wssix99

iTrader: (5)

It probably doesn't matter as long as you get a good connection. If you replace the entire wire, you'll need special equipment to put a new PCM connector terminal on the wire and fit it in. (So, its probably best if you splice it at some point.

BTW - You don't want to solder anything here. Connecting wires with soldered joints is not a good idea in cars, boats, or airplanes due to vibration. The joints are brittle, can crack, and spark. So, you'd want use weatherproof (shrink) crimp connections.


If you do this, you'll need new connector seals. GM has a TSB out on this connector and advises to replace the seals every time the connector is disconnected.

1 FMF

iTrader: (1)

why do you say this, or where did you hear that from?

a crimped connection that is not soldered is prone to corrosion, and boats are notorious for electrical problems as a result. electrical connections properly soldered are not prone to being brittle, cracking, or sparking. if that does happen it's because it's either a cold solder joint or the wire was not fluxed and you don't have good adhesion, and that's common with all tin based solders which require a higher temperature to melt. The standard 60/40 tin/lead solder can't be beat and is way stronger than a crimped connection can be, in fact it is stronger than the wire itself. Try soldering two 14-guage wires and hang on it, you'll break the wire somewhere else before the solder joint ever breaks. i even have ground wires that have been soldered in the boat that are exposed in the engine bay for the last 10-15 years with no signs of corrosion at the solder joint but plenty of it creeping elsewhere all along the wire.

wssix99

iTrader: (5)

This is common engineering knowledge. http://mechanicallugs.com/index.php/stranded-vs-solid Its not so much about the connection having solder and the solder being a problem - its the fact that solder makes a solid joint.

This effect is why all the wires on cars, boats, and airplanes, are stranded and not solid. Solid can't take the vibration like stranded can. When a wire is soldered, it behaves like a solid wire.

If you look at any car new from the factory, you will not find a soldered connection and this is the reason why. All splices, etc. have mechanical clips.

For repairs GM, and others, allow for some soldering, but you still have to have the mechanical connection so the strength of the splice is not relying on the brittle solder joint.


That's why the crimps below were invented and they come with any GM-sourced pigtail kit. The ends heat shrink over the splice and I recall that they also ooze a sealant during the shrink process: (If you can't find these at your local parts store, marine supply houses should have them.)

wssix99

iTrader: (5)

You are not considering the effects of vibration, which is the powerful actor here. Its an effect similar to bending a paper clip over and over again. You can't pull the paperclip apart with brute force, but if you bend it a few times, it falls apart like butter. (If you take pliers to that same 14 ga solder joint and bend it back and forth for a while, the same thing will happen.) Vibrations act the same way as bending the paperclip except they do it more subtly over a longer period of time.


If I were in your situation, I'd replace those wires or put a mechanical clip around the splice soon. The performance of what you have is all dependent on the vibration its exposed to. If you are wintering your boat and don't take it out every day, you may not have a problem for a very long time. With the greater use of the boat, the more vibration its exposed to, and the closer you will get to having a problem. The method by which the wire is secured can also have an effect. If the wire is free to flop around in the air and deflect more with vibration, the faster it will go.

Sparking is a much more serious issue on a boat because flammable vapors sink to the bilge and can't escape from the open bottom of an engine compartment on a car.

LS6427

iTrader: (2)

I never knew this. I've had my PCM tops off and back on a dozen times in the past 10 years.....seals are perfect. Just got my car back with the new engine and the PCM was removed and tops taken off to check inside again......seals are perfect and the tops went on perfectly.

.

wssix99

iTrader: (5)

Always good to look this up. Its been a while since I had this one open - it looks like the TSB I have for my car implies that this is only an issue for '99 and older, which have an aluminum body to receive the connector:

#83-81-32: INFO - NEW PCM CONNECTOR SERVICE KITS - (Sep 16, 1998)
SUBJECT: INFORMATION - NEW POWERTRAIN CONTROL MODULE (PCM) CONNECTOR SERVICE KITS
MODELS: 1996-99 ALL PASSENGER CARS EXCEPT GEO AND CATERA

TWO NEW KITS HAVE BEEN RELEASED TO SERVICE THE POWERTRAIN CONTROL MODULE (PCM) CONNECTOR IF THE CONNECTOR HAS BEEN DAMAGED DURING SERVICING. THIS PCM HAS AN ALUMINUM BODY AND IS USUALLY MOUNTED UNDERHOOD.

KIT (P/N 12167308) CONTAINS THE 80 WAY CONNECTOR BODY, THE COVER, TWO EACH OF FOUR DIFFERENT TERMINAL RETAINERS AND 25 EMPTY CAVITY PLUGS. NO TERMINALS ARE INCLUDED. IF TERMINALS ARE NEEDED, USE P/N 12084913 FOR .35 MM AND .50 MM WIRE AND P/N 12084912 FOR .80 MM WIRE. THESE TERMINALS ARE INCLUDED IN THE TERMINAL REPAIR KIT J 38125A OR B, AND REPLACEMENTS CAN BE ORDERED FROM KENT-MOORE.

KIT (P/N 12167313) CONTAINS ONE CONNECTOR SEAL. WHENEVER THE CONNECTOR IS UNBOLTED FROM THE ALUMINUM BODY OF THE PCM, THE SEAL CAN STICK TO THE BODY, OR MAY BE TWISTED. THIS SEAL SHOULD BE REPLACED WHENEVER THE CONNECTOR IS REMOVED IN SERVICE.

1 FMF

iTrader: (1)

gonna have to respectively disagree with most of that.
i wonder if this common engineering knowledge was started by someone marketing crimp connectors... if solid copper wire is prone to breaking from vibration like you mention, stranded wire is made up of a bunch of small diameter solid copper wire so why don't those break?
Vibration on a wire is not the same as repeatedly bending it 90° back and forth, the whole vibration thing is taken out of context and blown out of proportion. A soldered wire does not behave like a solid wire, i fail to see how that can happen. From a structural perspective the point where the solder connection ends on the wire is no different than where a crimp connection ends. the rest of the wire behaves no differently.
And I find it hard to believe those or any crimps were "invented" for this reason. Crimps, in my opinion, are an easier and many time more economical way to connect wires to connectors and plugs. At the manufacturing level where it's done by machine and the connection is sealed it's fine. No manufacturer is going to also solder the connections, the extra cost is not worth it. And regarding solder joints being brittle, that simply is not true. All circuit board electronics are a copper or tin soldered connection no different than what you are used to or what we are talking about, the connection is just smaller on a circuit board. consider the applications where those are used- everywhere, if this truly was an issue then we'd have transistors and IC chips falling off circuit boards but that doesn't happen.
I've seen plenty of electrical issues having owned a boat for the last 25 years and the scenario i had described was the bilge pump electrical connection. it's funny you mention how it's dangerous having sparks in a boat bilge, while i don't disagree you might consider a more practical aspect of having a bilge pump that never fails to a bad electrical connection which a crimped connection eventually will, I've seen it many times. Granted a lot depends on the quality of the crimp and other common sense factors, but a soldered connection just won't be compromised by corrosion like a crimped connection can and that's the greatest cause by far of electrical problems on boats not vibration or structural.

wssix99

iTrader: (5)

Its not. The mechanics and mathematics behind off this are complex, but all you have to do is a simple search for solid vs. stranded and you'll get a ton of good information:
http://en.wikipedia.org/wiki/Wire#Solid_versus_stranded
http://www.bdwires.com/solidwire.php

There's no conspiracy theory, either when you consider what's in every car out there. Some of the biggest penny pinchers out there are car companies, yet they put (more expensive compared to solid) stranded wire in every location in every car. Why would they do that?


(This is also why suspension cables on suspension bridges are stranded.) If you take a large diameter wire and a small wire and bend them with the same amount of deflection, the larger diameter will experience a greater stress at its outer edges. (where cracks start) The inner surfaces at the bend compress and the outer surfaces extend. On the larger wire, that extension is greater the further away the surface gets from the center of its cross section.

If you take a thick and think piece of round pasta, suspend them across a span and press them down the same amount, you'll see the thicker one breaks first, even though its "stronger."


The wires are the same. The solid cross section of the hardened solder acts like a solid wire. Its "different" but it acts the same.

You CAN use soldered connections. You just have to put a stronger mechanical splice around the connection as outlined in GM's wiring repair manual. A soldered connection is relatively weak compared to a solid crimp connector.



Those crimps were designed to be waterproof, which is a great option for this application.


This doesn't happen because the circuit board mechanically resists the vibration, so solid wires can be used and you may even find them on circuit boards in a car. If the wire doesn't move (like on a circuit board) there's no problem. If the wire can move with vibration, that's where the issue is.


BTW - I'm not talking about Home Depot plier crimps here. I'd only use a ratcheting type of crimper for these kinds of things. I agree that plier crimps are garbage and won't hold. But a quality ratcheting crimper will hold strong against some seriously strong pull-out forces.

1 FMF

iTrader: (1)

I gave up pasta, trying to lose weight. can you use a different food to describe how it relates to the topic at hand?
your going way off base with suspension bridges, maybe if the guy was building a suspension bridge with the wiring harness in the engine bay then maybe i could understand where you're coming from. suspension bridges use steel cable, i thought we were talking about copper wire? and i thought the initial argument was basically crimped connections are stronger/better than soldered ones- that soldered connections are brittle and break. I just don't agree with the perception you seemed to initially put forth about soldering copper wire which seemed to be you should never do it.
Consider military style (mil-spec) connectors, those you solder wire to the rear of the connectors. i would think if soldered connections were that bad then mil-spec connectors intended for the worst environments and applications would not allow soldering.

Mr Phil

To the op, what voltage issues are you having

wssix99

iTrader: (5)

You questioned solid wire fatigue being a part of common engineering knowledge. I was making the point that this issue is all around us and not limited to soldered wire splices.


Yea, its not about strength. Its a safety/reliability issue and is the reason why soldered splices (without mechanical reinforcement) should not be used.


Yea, its not that we should never solder wires in a car. Its that we should never use a plain soldered splice.


These are different and OK, because they eliminate movement of the soldered areas during vibration. The connectors secure the wires so they can't move under vibration, which a soldered splice will not do unless its mechanically reinforced.