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smlveightis

smlveightis

Confused in Confusion
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Feb 8, 2010
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Westland-Meechigan
The essentials:
1967 Barracuda FB, 273, floor shift A/T, Factory AC. Electric fuel pump, w/relay, & Battery Tender, are installed at the battery.
The story:
Every week, regardless of weather, I start, and let warm up my car. Gives me a chance to spend some quality time in the garage, with a couple of essential items of course, Beers and a cigar!
3 weeks ago (on Saturday), I installed my new tail light bezels. No issues at all.
2 weeks ago, I notice the Battery Tender "light" is Red. Battery posts had some corrosion going on, so I cleaned up both battery posts, and their corresponding cable ends, applied some dielectric grease, re-assemble, and wa-la! I get the Green light from the Battery Tender again!
Thursday evening, doing my usual routine in garage, step on brake pedal and notice only LH brake is lit (my normal operating procedure). I do some minor checking, and find out that I've got some type of wiring issue, and Sunday would be a good day to try and trace it down.
Today, I went to start the car to pull it out of the garage, and Battery Tender is showing Red again. I un-plug the unit (normal operating procedure), and turn key to start car, and I get nothing. No electric fuel pump, no exterior lights, no T/S, no starter, nothing! I do have courtesy lights, and the LH Brake light, but it seems weak, that's it! All three of the fuseable links look good, and I don't see any burnt/fried wires.
I am looking for a direction to go in, what flow chart of checking I should do. I am by no means an electrician, but I can usually fumble my way through a problem. I do have a meter, and a continuity tester at hand.
Any help is greatly appreciated.
Thanks in advance!
Steve~
 
What voltage do you have at the battery? Can you jump it to get it started? If so, do it and measure the voltage at the battery again. If battery measures 13.5 volts or more with the engine running, I would suspect that your battery has had it. Use a regular charger (10 amps or more) and charge for at least four hours. Disconnect from charger, let sit for an hour and measure its voltage again. If it is less than 12.5 volts, take it to a parts shop and have them load test it.
 
68gtxman, Thanks for the quick replay! V @ battery is 13.5 (initial flash of 13.5 when probes contact posts), then immediately jumps down to 7.90 V! I though that was weird! I'm starting to think my Battery Tender is the culprit. Before this post,
I had cleaned up the grounding strap locations in the engine bay, and got very dim headlights, weak fuel pump and wipers. I am going to put it on a different battery charger, then re-test V again @ the battery. Will post results in a while!
Again thanks fro the response!
Steve~
 
Try tending the battery with the cables unhooked. If your tender doesn't malfunction then you probably have a drain somewhere.

Maybe Del will chime in, he's the electrical guru around here.
 
I can tell you from experience that my 67 has always been finicky about the ground of the bulb socket to taillight housing. It has also been really finicky about using brass housing taillight bulbs to get a good ground for the socket. The newer nickle plated bulbs have a hard time gaining a ground from the socket/housing ground. Since you mentioned that you just did your taillight housings, maybe it is something in this area??

I also had a problem with passenger taillight and both brake lights working at all. I took a piece of info offered here and pulled my steering wheel and cleaned and debentures the contacts of my turn signal cam area, where all things taillight seem to happen! Cleaned and lubed that all up and the taillights and brake lights work like a charm now??

Is any of this your culprit?? I don't know, but its a good cleanup and reset for those often neglected areas and worthy of attention anyway!! I will mention that neither of our related problems had any effect on my battery charging system!!

Hope you can track it down...it sure is nice out today!! Geof
 
Sorry guys, I forgot to mention that the car also has a MP electronic conversion kit installed on it as well.
@ Bad Sport, I've got a regular (10A) charger on the battery now, w/o the battery cables. We'll see what ensues when I get it fully charged. I think you are correct, in part, about a drain somewhere. Maybe a combo of a bad Battery Tender, and a draw somewhere on the car. I will post results on that later.
@ Cosgig, I am definitely going to start going through the electrical system. Been long overdue, most likely, living on borrowed time! I already have a brand new enging bay forward harness, was going to install that when I drop my 340 in. Thanks for the suggestions Geoff. As soon as I can figure out the electrical demon causing the dead battery issue, I will do those items listed above.
Steve~
 
Clean the battery terminals, and connectors.. 90 % of my service calls for a "dead battery ,no power", just needed the terminals twisted to make the connection,, and then cleaned properly..

just a thought, often overlooked..
 
@ Inertia, I cleaned both battery posts, and corresponding cable ends 2 weeks ago, and they are still clean (see 1st post).
Battery took a charge, took it to local parts chain, and had it load tested. It checked out good.
I removed the Battery Tender terminal from positive cable end, and re-attached both battery cables. Turned the key and she started right up.
Going to start looking for a short now.
 
smlveightis said:
@ Inertia, I cleaned both battery posts, and corresponding cable ends 2 weeks ago, and they are still clean (see 1st post).
Battery took a charge, took it to local parts chain, and had it load tested. It checked out good.
I removed the Battery Tender terminal from positive cable end, and re-attached both battery cables. Turned the key and she started right up.
Going to start looking for a short now.
Click to expand...

I beg your pardon,, I missed it... cheers..

Do you have one of those replacement ends on the cable?
If so,, hope you took it apart and cleaned it too..
 
You guys are doin' fine without me, LOL.

So you've now got the battery charged and tested for certain.

It's possible the tender itself has gone south.

Next, disconnect the ground cable and put a small 12V test lamp in series. If you don't see a light, take your multimeter and put it on whatever scale is the largest range of current (if you post your multimeter brand model, we can look it up) and put it in series with the ground cable. If you read no significant current, drop the amp/ milliamp scale down a range or two and post the reading. Make sure EVERYTHING in the car is shut off, and if you have a hood/ trunk/ glove box light make sure those are all turned off.
 
67Dart273, very possible about the Tender gone bad.
I fully charged the battery (13.5V), and before I connected the positive battery cable took one last look at the terminal ends. Seems the positive end has a small crack in it, so I replaced it.
Per your instructions above, I connected positive cable, and hooked test light in series to the negative cable. No good light, just a quick flash of light. So I then checked for V in series, and it finally came down to .939V.
I then disconnected the positive cable and check battery V, that had come down to 13.2V. Should the Voltage of the battery drop/drain that quick?
Everything on the car is disconnected right now, including the fuel pump & relay, Tender, etc., and the key is out of the ignition. Where to next?
Thanks for any help on this!
Steve~
 
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