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Discussion Starter #1
I should be getting my 55 back from the uphostery guy Wednesday. My grandson and I are planning on joining a club cruise/show od Saturday. I need to chase down a drain In the electical. I suspect it to be headlight related. Frist time I was out using headlights is when the problem started. When I got home my high beams where real dim and the drain seemed to start at that time. I've been useing my battery tender to keep the battery up.
What method should I use to zero in the the problem circuit. It's a new factory fit harness.

Thanks in advance
 

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Bruce, do you have a voltage gauge in the car? What does it read with the engine running?

To troubleshoot the problem the first thing to do is remove the alternator "BAT" wire from the alternator. Put a test light or ammeter between the wire and the alternator BAT terminal. If it lights up or measures current flow, you probably have a bad alternator (bad diode draining current to ground). If not, leave it off for the next tests.

Next, remove the positive battery cable and put an ammeter or test light between the cable end and the battery and take a current reading or see if the test light glows. It should be zero amps unless you have a path to ground somewhere. Be sure to look at the test light carefully, because it may barely glow. An LED type is probably best for this (watch polarity).

If you get a current reading or the light glows, you have something conducting current. Start pulling fuses one at a time until the current stops. If it doesn't stop, try to figure out what other circuits are still powered and start disconnecting loads somehow until you find the bad circuit.
 

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Discussion Starter #3
Laszlo,

I do have a voltage gauge in the dash. I'll try the method you discribed. I was thinking of checking at the battery as you explained with a digital volt/ohm meter, It's a new alt but I'll start there just the same.

Thanks
 

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Trifive Automotive Electrical Wiring Expert
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With your great looking, :tu , EFI engine, you will see a little battery drain when you do the second test. You will see voltage because the ECM is connected to constant power. Also a late model radio with memory and a clock can draw current, but it won't run the battery down. Some meters have a 0 to 10 amp current scale that will indicate how much current drain.

As Laszlo mentioned, first make sure the battery is being charged, 14 or so volts at the battery while running.
 

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Bruce:
All modern cars and those upgraded such as yours always have a small amount of drain: on-board computer, radio, clock and other acesssories. This is referred to as "parasitic battery drain". The normal range should be about 0.035 amps. You can check the total amount of drain by unhooking one of your battery cables and installing an inline portable multi-tester. If you have an underhood light make sure you pull the bulb so this does not throw your reading out. If the drain is above normal you can reconnect your battery and then go to your fuse panel. Proceed by pulling each fuse and then jumping that circuit with your meter and check the reading. Continue checking each fuse until you narrow down the problem.

I had this happen on one of my vehicles and tracked it down to one of the electronic door locks.
For more info just GOOGLE " Parasitic battery drain"
Hope this helps.
ken 57
 

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I suspect it to be headlight related. Frist time I was out using headlights is when the problem started. When I got home my high beams where real dim and the drain seemed to start at that time.
................ It's a new factory fit harness.
Bruce, I don't think it's headlight related. Dim headlights are a result of the problem and not a cause.
After rereading your post, I think you have a chargeing problem and not a battery drain. Even with a battery drain, the headlights will not dim with a 100+ amp alternator as long as the engine is running. It's almost a dead short if it dims the headlights. The switch disconnects the lights when it's off, which will eleminate any problem with the headlight wiring.

P.S. with a factory fit original wiring harness, there are some devices that were not originally fused, so pulling the fuses won't eleminate everything. Cigrette lighter, clock, wiper wiring, and ignition circuit.
 

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"Cigrette lighter, clock, wiper wiring, and ignition circuit."

Hopefully these and any others are now fused. They really need to be, especially on a high end car with factory EFI swapped in. The swap should have taken care of fusing the ignition. The others are very easy to fuse separately if need be.
 

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"Cigrette lighter, clock, wiper wiring, and ignition circuit."

Hopefully these and any others are now fused. They really need to be, especially on a high end car with factory EFI swapped in. The swap should have taken care of fusing the ignition. The others are very easy to fuse separately if need be.
 

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Discussion Starter #10
Bruce, I don't think it's headlight related. Dim headlights are a result of the problem and not a cause.
After rereading your post, I think you have a chargeing problem and not a battery drain. Even with a battery drain, the headlights will not dim with a 100+ amp alternator as long as the engine is running. It's almost a dead short if it dims the headlights. The switch disconnects the lights when it's off, which will eleminate any problem with the headlight wiring.

P.S. with a factory fit original wiring harness, there are some devices that were not originally fused, so pulling the fuses won't eleminate everything. Cigrette lighter, clock, wiper wiring, and ignition circuit.

I picked up my car yesterday had to jump start. Got back to work and put a 10 amp charger on it for a couple hours. Had to jump it again. Rand like crap on the way home dash meter read 14 amps. Checked for a drain with volt meter. I put it between the neg battery cable it read 8.46. I pulled every fuse disconnected my stereo amps and no change. My plan is to look at the cable on my starter next?
 

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I picked up my car yesterday had to jump start. Got back to work and put a 10 amp charger on it for a couple hours. Had to jump it again. Rand like crap on the way home dash meter read 14 amps. Checked for a drain with volt meter. I put it between the neg battery cable it read 8.46. I pulled every fuse disconnected my stereo amps and no change. My plan is to look at the cable on my starter next?
Hi Bruce,

When you said the "dash meter" read 14 amps, did you mean your voltmeter read 14 volts? If so, it appears your alternator is working.

You can't check the battery drain with a voltmeter, you have to use it in ammeter mode. You need to measure amps (current), not volts.
 

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Discussion Starter #12
Hi Bruce,

When you said the "dash meter" read 14 amps, did you mean your voltmeter read 14 volts? If so, it appears your alternator is working.

You can't check the battery drain with a voltmeter, you have to use it in ammeter mode. You need to measure amps (current), not volts.
Hi Laszlo

Yes its 14 amps on the dash. I may be using volts on my volt ohm meter. I'll dbl check that. My mind just wasn't with it last night.

Thanks!
 

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Trifive Automotive Electrical Wiring Expert
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Checked for a drain with volt meter. I put it between the neg battery cable it read 8.46. I pulled every fuse disconnected my stereo amps and no change. My plan is to look at the cable on my starter next?
You will ALWAYS see voltage between the neg cable and battery until you disconnect the EFI computer, clock, and anything else that can draw current.
I still think your battery is not fully charged. The alternator may be trying to charge it, but it is not taking a charge. What is the voltage across the battery with the engine off? If it's a jel cell battery, it may take a trickle charge for days to bring it back from dead.
I'll bet that's a voltmeter on the dash. :)
 

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Discussion Starter #14
You will ALWAYS see voltage between the neg cable and battery until you disconnect the EFI computer, clock, and anything else that can draw current.
I still think your battery is not fully charged. The alternator may be trying to charge it, but it is not taking a charge. What is the voltage across the battery with the engine off? If it's a jel cell battery, it may take a trickle charge for days to bring it back from dead.

Yes it's a red Optima. Last night all I could get accross the battery was 8.4 volts. I took it for a short drive. stated with a jump and when I got back from my 2 mile loop it wouldn't even pop the trunk
 

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Yes it's a red Optima. Last night all I could get accross the battery was 8.4 volts. I took it for a short drive. stated with a jump and when I got back from my 2 mile loop it wouldn't even pop the trunk
Sounds like maybe a bad battery. If your alternator is putting out 14 volts, but the battery only reads 8.4 volts without a load, it's gotta be bad or it's not charged correctly. I have read that these Optimas are finicky to charge.
 

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Discussion Starter #16
Sounds like maybe a bad battery. If your alternator is putting out 14 volts, but the battery only reads 8.4 volts without a load, it's gotta be bad or it's not charged correctly. I have read that these Optimas are finicky to charge.
It was a new battery when I bought it 1 1/2 years ago :). I may just buy a new one. That would get my grandson and I to the cruise this weekend
 

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Discussion Starter #17
You will ALWAYS see voltage between the neg cable and battery until you disconnect the EFI computer, clock, and anything else that can draw current.
I still think your battery is not fully charged. The alternator may be trying to charge it, but it is not taking a charge. What is the voltage across the battery with the engine off? If it's a jel cell battery, it may take a trickle charge for days to bring it back from dead.
I'll bet that's a voltmeter on the dash. :)

Yes, Sorry it's Volts
 

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Ran like crap on the way home
A bad battery could also explain the rough running. EFI's don't like to run on the alternator alone, if the battery is not smoothing out the voltage.
PS: I like that dash, especially the A/C vents up high like that. :tu
 

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The optima charged curse,,been down that road.

This is some interesting reading. I have used the procedure described here,,it does work, you just have to have a charger that will put out 60-80amps. I zapped two yellow tops back to life using this exact method, they were 2 years old. I used the 75 amp start/charge selector on my charger. A lesser start/charge selector will just take more minutes per cycle.
http://www.batteriesareus.com/index.php?main_page=product_info&cPath=113_46&products_id=157

There are alot better batteries out there than the optimas now. I had a A/C Delco 7 year battery that went 9 years before needing replacement. I replaced it with the same.
http://www.acdelco.com/parts/battery/professional-battery.jsp
 

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The problem with wet cell batteries, they should not be used in the trunk unless it is sealed from the passenger compartment.
 
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