Altenator, fusible link, ABS, woes!

[bowtiebutch]

I bought the 97 3.1 Grand AM SE new in 97. Since 99 I have gone through 6 alternators and batteries. This car has had the electrical system tested three times and always checks out O.K. The last test was performed last week. The alternator replacements were from different sources also the batteries. Lately the fusible link from the starter to alternator has been burning out thus protecting the alt. I have had an intermittent ABS light previous to burn out but get no indication of alt problem. The last electrician indicated the problem may be in the starter. I have changed the starter and so far no burn out of alt or link but still get ABS light occasionally. I have been told late model GMs are prone to cracks on the reluctor rings for the ABS sensors and can cause a direct short to ground. Any truth to this?
I hate to drive too far as afraid I'll get stranded and be in for another tow bill. The OBD II has no stored codes. Any ideas what to look for? All help greatly appreciated. Thanks

[rixGAphx]

CHECK THE BATTERY AND ALL ITS CONNECTIONS!!!

1. The GA's electrical system is VERY susceptible to minor variations of voltage, resistance, and load/amperage.
2. Disconnect the negative terminal first, then the positive; when done, reconnect pos first, then neg (this avoids accidental sparking if the wrench slips and hits a metal body/engine part while turning the pos screw).
3. Clean all terminals to shiny metal; remove deposits with a water/baking soda solution, and sand/scrape/polish the metal with sandpaper and knife.
4. The molded red rubber boot on the positive battery terminal allows massive corrosion to develop unseen within the boot.
This happened to me, and it FRIED the alternator (the alternator 'sensed' a dead battery and tried to put out maximum amperage for recharge, but the power couldn't get thru the corroded connection).
IMO, cut off this crappy GM rubber boot, and replace with an aftermarket protective cover that can be inspected.
5. Reconnect the neg terminal last.

I firmly believe that at least 50% of all GA electrical-related problems will be solved by proper and MONTHLY attention to the battery as stated above.

Just passing on my experience.
-Rick

PS - bowtiebutch: The ABS system is one of the most sensitive to bad current flow. The indicator light will come on if the battery is just low (from something like partial battery drain due to listening to the CD with engine off).
I don't know about the reluctor problem, but I would *think* a short-to-ground should blow the ABS system fuse before any further damage occurs.

[tenspeed]

All I can add to Rick's excellent reply is that I coat all surfaces with an electrically conductive grease that is used for copper / aluminum connections. I'm an electrician and have been doing it on all sorts of electrical connections on my cars.

The grease can be bought at electrical supply outlets and maybe some of the home improvement stores. It's basically petrolum jelly with zinc powder added to aid in conductivity. It seals the connections from oxidation.

[rixGAphx]

Originally posted by tenspeed
...to Rick's excellent reply..
:D :D :D Thanks!

All I can add is that I coat all surfaces with an electrically conductive grease that is.....basically petroleum jelly with zinc powder added to aid in conductivity. It seals the connections from oxidation.
Good tip.

[bowtiebutch]

Appreciate all ideas and thoughts. After double checking to make sure I have good clean connections I re-routed the battery wire (fusible link) from the alternator to starter. I disconnected it from the starter and made a direct connection to the + poat on the battery thus eliminating any possibility of resistance in the battery cable. I am now charging directly from alt to batt. So far no lights of any kind today and the battery is maintaining a charge. Keep your fingers crossed. Thanks again

[bowtiebutch]

Well it's been a while since I made the corrections and guess what, burned out another fuse link yesterday. I have now pulled the fuse from the abs. This problem has been addressed numerous times and as to date no one even Pontiac can't figure out whats going on. Any other ideas? Thanks

[rixGAphx]

Sorry to hear the problem is ongoing.
I have no further thoughts at the moment, but I'll ponder it for a bit and report any bright ideas.

-Rick

[pfofit]

What size link are you using and where are you getting them. Is there a possibility that they are flaky or are they different manufactorers.

Have you/ anyone put a dc clamp meter on this alt to batt cable for an extended time to determinethe actual current in the wire. ?

When you rerouted the alt wire directly to the bat instead of the tie in at the starter did you check the entire length of the wire for damaged insulation melted /cracked.

that link should handle a signifcant current and therefore if some sensor or shorted wire was the problem the lower current fuses that protect these systems should vaporize way before the link that supplies charging current to the bat.

Have you check the connection/wire between the bat and the power distribution box for corrosion or insulation problems?

very wierd

Since you've have numerous bats and alts and even the strater, it does not make sense,... yet.
Very Weird

Good luck

[rixGAphx]

Originally posted by pfofit
...That link should handle a signifcant current and therefore if some sensor or shorted wire was the problem the lower current fuses that protect these systems should vaporize way before the link that supplies charging current to the bat....
UNLESS, the short is thru an unfused, always-hot circuit.
* Starter motor.
* Headlights (auto-resetting circuitbreaker).
* An added-on audio circuit, over-fused?

-Rick

[pfofit]

rixGAphx. So true!

Buddys problem is very strange, I would love to have that car sitting in my driveway for a couple of hours so i could take a kick at the can. I love these sort of detective type snot problems.

Anything add on is suspect for me cause most never fuse or improper wire/fuse combo, no gromets, or wires running to close to moving parts.. Although he has not mentioned any add ons and of coarse we have not asked. Well i guess we just did.


I wonder if when the starter was replaced, was the solonoid replaced as well?

[bowtiebutch]

Thanks for the interest. There are no add-ons completly stock. The fuse links are Buss brand bought from different suppliers and are 14 ga. (same as original). It protects the 10 ga wire from the alt. It either burns the 14 ga or the solderless connector connecting the two together.

All connections are clean and no corrision. Does anyone know the max ampreage the fuse link will take. The starter and solenoid have been replaced.

It seems as if I get a ABS light then the problems start. I have removed the 40 amp ABS fuse. I'm trying to isolate the problem. Ever heard of a faulty fuse? It's the oridginal. I have inspected the wire to alt no signs of faults. It is not shorted to ground.

Guess I'll keep on plugging away until I find it.

[bowtiebutch]

I bought a digital clamp on amp meter. The readings are as follows, with the engine cold everything on (lights, radio, etc.) it draws 69 amps (link gets hot but dosen't melt) as engine warms up it drops to 53 amps (link barely warm). When the cooling comes on it draws 60 and the link warms up. With everything off it draws mid 30s amps. The battery is charging at 14.25 volts and holding a charge. These readings were taken with the 40 amp ABS fuse in and out, (no difference). I did notice acid on the battery tray and the battery was damp I cleaned the tray and wiped down the battery (maybe it was too full of electrolyte). The only thing left would be to swap out the alt wire for a new one, eventhough it has good continuity and is not shorting to ground. Maybe it is breaking down under load. I'm still no further than I was in 1999 when the problem began.

[rixGAphx]

Have you opened that damned red rubber boot on the cable of the battery positive terminal?
The cable corrodes UNSEEN inside of it, and reduces the current capacity immensely.
The alternator will 'compensate' by trying to push more amps to a battery that seems dead.

-Rick

[bowtiebutch]

Yes I opened the rubber boot and it is clean as a whistle along with all elec connections. Thanks again

[bowtiebutch]

In regards to my last posting the alt wire is connected directly to the battery thus eliminating any chance of a poor connection at the + cable connection. I installed the fuse link connection next to the battery then screwed on the cable connection bolt. So far it's working except both the link and alt wire get hot but haven't burnt out yet but then it's only been a day.

[HeyDace]

Has anyone checked engine to body grounds, Battery to body? Neg. post to block? Some aftermarket alt's need an additional ground wire from the case to block.

[bowtiebutch]

All grounds have been checked and re-checked. I have ground to bare metal to assure good grounding. I installed a ground from alt case about a year ago. I ground the paint from the alt brackets as this was the source of some late model gm's. Still have same problems. Thanks for your input.

[4kQuad]

:penny:
A friend had problems with a car once after he removed the Extra little wire that runs from the - on the battery to the car body. No not the big one all cars have, but a extra little one.

I don't remember the whole story, but I remember lots of eletrical problems. Mostly in charging.

For the few cents it would cost, I would try replacing the wire that gets warm/hot at higher loads, then cools at lower loads. There may be week points in the wire, some thing has to be causing it to get hot/warm with a load change. I mean for the size of the wire, there's not much going through it.

Since 1999, man there must be forehead shaped bang marks in the garage walls. j/k.

Dumb question, but are the connections at the starter clean?
Another dumb question. Are you sure the pully on the alts are the correct size?

Does the ground wire from the battery to the frame/motor where ever it goes on your car also get hot when the other lead does?
My thinking here is if another wire gets hot at the same time, maybe there is a clue there.

Sorry I really don't have anything good for you, but that's my :penny:

[pfofit]

40 amps with everything off seems maybe a bit high. Did you try the clamp on the bat to power distribution wire. Subtracting these two currents will give you the charge going to the bat. Once the bat is charged the current to the bat should drop below 10 to like 5 or something.

Once the bat gets charged/car warms up, and all off you can try pulling fuses on non essential circuits like lights, cigerette lighter defroster etc. to see if the static current goes down when an "off" circuit gets disconnected. Of course don't pull em with the car running. Unless your brave, whicjh i am not .


Also those links not only have to be the same wire size but also the same length as the original. If the length is too much longer than the original that may account for the warming. 70 amps is not unreasonable with all circuits drawing.

A 14 gauge wire by itself can only hold safely about 15 amps, however, when it is only a few inches long it acts like a fuse with a much higher rating and properly matched should not get hot enough to melt itself or the connections. The longer the link becomes the lesser is its maximum current rating becomes. If it gets long enough, a 14 guage link will become a 14 guage wire and overheat. I'm sure you probably know this, just thinking out loud

good luck.

Isn't a clamp on ammeter just a wonderful thing, takes a lot of guess work out of the problem.

[bowtiebutch]

The wire that get's hot is the wire from bat side of alt to + side of bat, it is 10ga protected with 14ga fuse link. This seems to be the only wire that heats up. I plan on changing both this weekend when my daughter brings the car back. Connections at starter are clean. The pulley is same diameter as original, one of the first thing I checked.

The wire that feeds the power distribution fuse box has the same readings. I have pulled the fuses to check for a ground and while engine is running. After I change the alt wire I'll check again.

I don't know how long the original fuse link was as it was burned out from connector to connector (I installed the new at about 5" long maybe too long). Not only does the link get hot but a couple of inches from the connector the 10ga also gets hot, hot enough to melt the insulation, but not the full length approx 3ft.

I plan on buying a new hydrometer to check battery cells. I replaced the maintence free bat with a standard type ( about the 6th one since 99).

The clamp on was a good investment should have bought one years ago. I also purchased a OBDII code scanner you just never know. Again thans for all input.

[rixGAphx]

Instead of a fusible link, you *could* run cable of adequate gage for the load, and install a replaceable inline fuse of proper rating.

[bowtiebutch]

I was going to do this sometime back but I don't know what size fuse to use and of course Pontiac was no help. It's still a good idea. I'm going to swap out the 10ga wire this weekend and shorten the link. Thanks

[pfofit]

The fusible link tends to act like a slow blow fuse whereas an inline fuse is a quicker acting device and will probably pop easier with surges.


The problem with an inline is that the alt is probably capable of pumping out up to a hundred amps and would result in a bulky affair.

I bought fusible link wire in a ten foot roll and most alt links i've replaced were about a few inches, haven't done one in a while so i'm a little foggy. How are you making the connections? Crimps, solder or both? As you probably know, any bad connection will create a high resistance and with these kinds of current, heat.
Nevertheless with the 70 amps you measured with everything going, that link should not be getting hot

Do you know anyone with a similar car that you can pop the hood to check the length? I don't have a GA or i would go check my own. Perhaps someone else can take a look see at theirs for the length?

good luck and keep posting.

[rixGAphx]

Originally posted by pfofit
Do you know anyone with a similar car that you can pop the hood to check the length? I don't have a GA or i would go check my own. Perhaps someone else can take a look see at theirs for the length?
I have a '96 with 3.1, so it might be similar.

Despite all the friggin' problems I've had, I've not encountered this fusible link.
Where would I find it to measure it?

-Rick

[pfofit]

It is at the tie point on the starter stud where the big red wire from the bat meets the black wire from the alt. The link is on the black alt wire.

You will see a narrowing of the wire size with heat shrink at the splice and will probably have "fusible link ## gauge" written on the narrower piece

[bowtiebutch]

According to the elec diagrams 96-98 are all the same. The fuse link is gray attaching to the 10ga red wire on the starter's larger post where the bat cable is attached. It's kinda tough to get at without jacking up the front end. Thanks for your help.

[bowtiebutch]

I forgot to mention I have been using solderless crimp connectors. Last time it went the plastic insulation on the connector disinegrated and the insulation on the 10ga wire overheated . I think solder would just melt.

[pfofit]

solder melts between 360 F and 500 depending on type. Rosin core is best for wires as acid core will corrode

[rixGAphx]

I examined my '99's fusible link today.

By sight and hand from above, the lead from the starter 'hot' terminal to a hefty connector is 4 inches.
I couldn't see any writing.
The diameter of the insulated cable *appeared* to be that of 6 gage conventional insulated wire.

After the wire connector, the cable went directly into the ribbed plastic wiring protector, so I couldn't see where it went nor what size the cable out of the connector was.

I don't know if these observations are of any help.
-Rick

[bowtiebutch]

If the 4" wire is gray then it's the link it runs through the wire loom to the alt which can't be traced without removing the loom. Thanks I'll shorten the link and see what happens.

[bowtiebutch]

The response below was from another club does anybody know what he's referring to? Thanks

Well the abs might cause brake problems but it will not cause you to be
towed...Another possible problem would be alternator circuit voltage drop or
uninuslated circuit voltage drop causing overcharging... and burn out..