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Discussion Starter · #1 ·
The battery in my 99 Sub died a couple of weeks ago. I bought and replaced it with a new one. A couple weeks later that battery started to act up and finally died. I took it back, they tested it and said it was bad. And now I have a third battery in it. I noticed that when I lock the doors from the inside using the electric door lock button, the door locks click on and off a couple of times and I can hear clicking coming from under the driver side dash (relays?). I'm thinking maybe the battery/door lock problem is related.

Anybody have a clue on how to debug this, or have a 99 Sub wiring diagram?

Thanks!!
Tim
 

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You may have a relay that is sticking, and creating a battery draw. Do you know how to check for a draw?

If so you need to check 1- if there is in fact a draw, 2- then if there is a battery draw you need to start to eliminate circuits to pin point the draw, then check that circuit for the problem.....

It's not that easy to find a battery draw!!!!!
 

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Troubleshooting dead/dying battery can take some work. Here is a place to start. Goto: Shadetree
Here is an excerpt:
[FONT=Arial, Arial, Helvetica]Two of the most common problems we see include:
“Parasitic Current draw”, where the battery goes dead with the vehicle shut off for extended periods of time.
“Poor Component Operation”, such as headlights flickering or having low intensity, or stop and tail lights malfunctioning.
[/FONT]
[FONT=Arial, Arial, Helvetica]Let’s start with a diagnosis of the current drain on a battery:
If a known good battery is fully charged, placed in a vehicle and then discharges in a specific time frame (Let’s assume overnight), the most likely cause is a “current draw” not a short circuit. (If you have ever grounded one end of a wrench while removing or installing a positive battery post with the ground cable hooked up, the resulting sparks, burnt hands, and melted cables are the classic “Short Circuit”.
[/FONT]
[FONT=Arial, Arial, Helvetica]To check for a current draw, disconnect the negative or ground battery cable and connect a 12 volt test light between the battery and the battery post. With all accessories and the ignition switch off, the light should not glow. If it glows, there is a current draw. To isolate the source, start by unplugging fuses. If the light goes out when a fuse is removed, you have found the circuit that is draining the battery.[/FONT]
[FONT=Arial, Arial, Helvetica]Be sure the hood light is unplugged (if equipped ), and all the doors are closed. Then follow the service manual or schematic to locate which items are powered by that fuse and begin to isolate them.[/FONT]
Let us know what you find. Don't forget to check for bad chassis ground, especially if you have had the vehicle painted.
 

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are you sure your altanator is good? i was on a trip going to Lego land with the family and found out i had a tost altinator. the shop was in Glendale and i was next to him as he built me a new one. he said these alts are junk and like to eat bearings and voltage regulators. i did find there are 2 typs a 102 amp and a 128 the mounting is different and plugs are different but with a good shop they can get the 101 to push 134 amps. we bench tested my new one and it is 14.75 volts with 134 amps. alot of little things went away after the swap. the speedo does not bounce. all the guages do not bounce with the turn signal on. the radio light does not go low and high and for some reason i got 4 MPG better after the swap. i had done this on the road so i did not get pictures and do a writeup but i can do a simple writeup if it is wanted and add current pictures...........mike
 

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Discussion Starter · #5 ·
First of all, thanks so much for all the replies - good advice!

The new battery I put in 3 weeks ago is still holding a good charge. The charge indicator in the dash is showing 12-14 volts and the Sub fires right up each time. If there is a problem, it appears to be intermittent, or maybe it was actually a bad battery right from the store.

I put a volt meter on the battery terminals with the engine running and it read a solid 14 volts. At least it appears the alternator is working properly.

The postings on how to diagnose a current draw make perfect sense and I'll follow those recommendations the next chance I get. I'll check to see if I even have one.

Thanks again for all your help guys!
 

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lights pulsating

are you sure your altanator is good? i was on a trip going to Lego land with the family and found out i had a tost altinator. the shop was in Glendale and i was next to him as he built me a new one. he said these alts are junk and like to eat bearings and voltage regulators. i did find there are 2 typs a 102 amp and a 128 the mounting is different and plugs are different but with a good shop they can get the 101 to push 134 amps. we bench tested my new one and it is 14.75 volts with 134 amps. alot of little things went away after the swap. the speedo does not bounce. all the guages do not bounce with the turn signal on. the radio light does not go low and high and for some reason i got 4 MPG better after the swap. i had done this on the road so i did not get pictures and do a writeup but i can do a simple writeup if it is wanted and add current pictures...........mike
Yes, I would like more information... I am going to replace my alternator. My headlights and dash lights have been pulsating. Has any one else had this problem? I dropped in a new battery, but that didn't fix it, The battery is getting a good charge (according to Sears and the dash meter). I am counting on it being the regulator in the alternator that is going bad. Any suggestions?
 

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Yes, I would like more information... I am going to replace my alternator. My headlights and dash lights have been pulsating. Has any one else had this problem? I dropped in a new battery, but that didn't fix it, The battery is getting a good charge (according to Sears and the dash meter). I am counting on it being the regulator in the alternator that is going bad. Any suggestions?
Bad grounds can cause light flickers also. Check ground at engine to firewall, lights to radiator support. Battery to frame ground.
 

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new alternator did the trick...

Yes, I would like more information... I am going to replace my alternator. My headlights and dash lights have been pulsating. Has any one else had this problem? I dropped in a new battery, but that didn't fix it, The battery is getting a good charge (according to Sears and the dash meter). I am counting on it being the regulator in the alternator that is going bad. Any suggestions?
Just an up date (to help any one that ever has the same problem). The new alternator fixed the pulsating lights problem, the meter on dash does not shimmy or shack either. Even though Sears said the alternator was good and the meter on dash said it was getting a little over 14.
Thanks for the help 84fiero123!
P.S. For all the newbees like me, use a socket rench (with out the socket) to push down the tensioner, to pull off the belt. It fits nicely into the square hole. I didn't figure this out until after I had taken the tensioner all the way off and noticed the square hole. Live and learn!:great:
 
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