nimrod.sixty9

iTrader: (5)

Volts have always gone between 13.5 ~ 12 (according to gauge), and the headlights and others have always flickered. I mentioned ABS INOP etc. just incase they may be related.

To me that said 'lose\dirty ground'. I had already checked all the grounds (except the one that are on the heads because I couldn't find them).

Today I noticed that the (for the first time) volts went all the way to 9 ~ 10, more than once.

So tonight I decided to add a big *** ground cable. I went from the ALT bracket to the strut tower bolt. I made extra sure that all the contacts were sanded and cleaned.

When I started her up she hovered at 9 ~ 10 and then went to about 14 then slowly came back to where its always been. And of course, headlights still flicker.

So still no change...

I went and had my battery and ALT tested and all results came back great...

So WTF do I do now?

https://ls1tech.com/forums/general-m...lant-help.html

Tom (theguyulove2hate) will be emailing me all my codes very soon. So Ill post them up as soon as I get them.

jam01

how are the battery cable's, the battery and have you checked the alt. try testing them.

n2ocamaro

The ABS INOP light is due to the low voltage. Fix your voltage problem and that will probably go away.

fleetmgr

Flickering lights usually mean that you have a bad diode in the rectifier. Doesn't mean that the alt won't put out voltage, but it's close to being dead.

nimrod.sixty9

iTrader: (5)

Cable contacts are good at the battery.
I did have the batt and alt tested (see post). Both came back as good.

I hope this is the case. But I have a lot more lights on than this. I cant remember the exact code that was pulled but its something along the lines of a communication loss between ECM and ABS. I think U0121...

Sounds like your possitive of this. So my next step is to get a new ALT even if it tests good?

fleetmgr

That would be where I'd go next. Without going into the rectifier to actually measure the diodes with an ohmmeter (which means unsoldering the little beggars on one end 'cuz you can't measure across them in circuit), or hooking up an oscilloscope to look at the output waveform from the alt you're kinda between a rock and a hard spot.

nimrod.sixty9

iTrader: (5)

I will get another alt asap. You think it may fix my INOP ABS ASR etc...? Im a little doubtful as the last owner said they have been on for years...

fleetmgr

As they've been on for some time, it may not. Which would mean you have more troubleshooting to do to find out why.

nimrod.sixty9

iTrader: (5)

http://www.autozone.com/autozone/catalog/parts/partsShelf.jsp?displayName=Alternator&itemId=86-0&isSearchByPartNumber=&sortType=null&totalPages =[I@577481&currentPage=1&vehicleNValue=&navValue=164 00086&parentId=64-0&fromString=&fromWhere=null&filterByKeyWord=&cate goryNValue=&categoryDisplayName=Starting+%26+Charg ing&_requestid=500346

^^^Think the cheaper alt will be fine? Its all I can really afford.

fleetmgr

The cheaper one will do, just make them prove it works before you bring it home. The stories of DOA remans abound.

nimrod.sixty9

iTrader: (5)

Thanks for the tip. Never even thought to have them test it before I left the store! Thank you

I should also note that its a fast flicker. Not a dim down. The AC blower motor or anything else I can think of doesnt die down at all. Just all the lights and the gauge.

Why would I have a status of good when I had the ALT tested? I seen 14.7 on the screen, but I dont know which that was for. I was just looking over shoulder....

fleetmgr

Alt's produce AC, which must be rectified into DC to be useful in a car. They do this using what's called a bridge rectifier. When one side of the bridge goes bad you still see output, but only for 50% of the A/C cycle. The other 50% is dead. This is what makes the lights flicker. It's also why the alt will show output, even though it is in fact bad. Most meters can't physically react fast enough to pick up the bad rectifier. They just show a lower than normal output.

nimrod.sixty9

iTrader: (5)

Just to let you know its a random rapid flicker. No pulsations at all.

Whats this exciter wire about?

fleetmgr

Alt's need a small charge to allow them to produce juice, and the exciter wire does this by getting 12v from the battery.

breNt*

iTrader: (1)

i have a somewhat similar problem.. 4 alternators later and didn't fix anything.. even though i was told by everyone and their brother it was my alt.. 4 brand new ones too..

nimrod.sixty9

iTrader: (5)

Glad you told me to test before buy. Sure enough, AZ has the only one in town and it failed all tests.

I barely got home from work when the bat completely died. Snagged the one from the other car and it still read low. Then all of a sudden it jumped right back up ESH!

I checked the exciter wire and all connections, everything looks good. So now Im about to head out of town to get an ALT.

Wish me luck.

nimrod.sixty9

iTrader: (5)

Well its been a few days with the new ALT, and I was sure it was fixed. But sure enough last night I saw it dim and rebound. Seen the voltage drop all the way to 12. What I find strange is when I first got it it hovered around 14 then slowly made its way to a hair above 13. Usually it seems to start off at 13.5 then by warm up its at 13.1....

When I changed the alt I checked all positives and grounds... So what the **** is next

One thing for sure is that its only done it twice since... Before Id lose count around five minutes or so...

01PewterMadre

iTrader: (4)

I had the same issue (flickering lights -dash and headlights) so i decided to check the alternator. The alternator failed so I replaced it with a new one and that fixed that problem. I also got a new battery

nimrod.sixty9

iTrader: (5)

New alt new batt new belt

lookin4aTA

What are our alternators rated at? I just got a new one and it will start out around 13 volts but then drops down to 10.5-11 and just sits there. The one I got was a 210 amp. Is that right