HELP Parasitic drain killing battery; Prize if you find a solution
12-16-09, 08:08 PM
#1
HELP Parasitic drain killing battery; Prize if you find a solution
Alright I've had a parasitic drain for awhile now on my '94 SC400 and it is getting really frustrating. Here is a thread from when it started https://www.clublexus.com/forums/per...overnight.html
Since then, I've gotten a new battery and a battery brain. The battery brain disconnects my battery before it completely dies, so I don't need a jump it constantly. It definitely helps but I'm sick of reprogramming everything and having the ecu constantly relearning. Also, I cannot commit myself to modding a car with an annoying problem like this.
I've already been to one mechanic but he didn't do anything that I couldn't and I got charged way to much. So, I'm asking for your help (or any of your friends help). Anybody that knows the SC like the back of their hand, is really good with electronics, or someone that is really good with this type of problem.
I've been trying to figure it out for myself and can give anyone that is curious more details. It usually takes 2+ days of sitting to die but the last couple of weeks the battery brain has been disconnecting it every night.
I've been reading a draw of 70-80ma which is a little high but I don't think that should be draining the battery this fast.
I don't really want to keep paying people upfront and in the end have no progress, so I'm asking for your help. Anyone that can figure this out or fix the problem can pick one item from the list below or we can work something else out beforehand if you're not interested in anything.
HELP!!!!
Prizes:
Pair of SC Headlights
Pair of '92-'94 red-out taillights (could use some cleaning)
SC300 manual cluster (rare w/ approx. 70k miles - Needles out)
Pair of extra headlights lens that I was delining
SC400 oem shocks and springs assembled (approx. 120k - fronts may be blown)
Since then, I've gotten a new battery and a battery brain. The battery brain disconnects my battery before it completely dies, so I don't need a jump it constantly. It definitely helps but I'm sick of reprogramming everything and having the ecu constantly relearning. Also, I cannot commit myself to modding a car with an annoying problem like this.
I've already been to one mechanic but he didn't do anything that I couldn't and I got charged way to much. So, I'm asking for your help (or any of your friends help). Anybody that knows the SC like the back of their hand, is really good with electronics, or someone that is really good with this type of problem.
I've been trying to figure it out for myself and can give anyone that is curious more details. It usually takes 2+ days of sitting to die but the last couple of weeks the battery brain has been disconnecting it every night.
I've been reading a draw of 70-80ma which is a little high but I don't think that should be draining the battery this fast.
I don't really want to keep paying people upfront and in the end have no progress, so I'm asking for your help. Anyone that can figure this out or fix the problem can pick one item from the list below or we can work something else out beforehand if you're not interested in anything.
HELP!!!!
Prizes:
Pair of SC Headlights
Pair of '92-'94 red-out taillights (could use some cleaning)
SC300 manual cluster (rare w/ approx. 70k miles - Needles out)
Pair of extra headlights lens that I was delining
SC400 oem shocks and springs assembled (approx. 120k - fronts may be blown)
12-16-09, 08:46 PM
#3
Only aftermarket components are the battery brain, alarm, and HIDs. All were added after I discovered that I had a drain; so they are not the culprits.
One thing to note is that the stock alarm wasn't working when I got the car and it would sometimes go off randomly. I put an aftermarket alarm to try to override the stock one and correct any problem.
One weird thing is that every once in while if the alarm is triggered both the aftermarket alarm and the stock alarm sirens go off. Should this happen? Does everyone else completely disable their alarm when installing an aftermarket one?
One thing to note is that the stock alarm wasn't working when I got the car and it would sometimes go off randomly. I put an aftermarket alarm to try to override the stock one and correct any problem.
One weird thing is that every once in while if the alarm is triggered both the aftermarket alarm and the stock alarm sirens go off. Should this happen? Does everyone else completely disable their alarm when installing an aftermarket one?
12-17-09, 08:03 AM
#5
Another thing is that the drain drops to about 20-30ma when I remove the "dome" and "radio 1" fuses under the hood. It doesn't drop if I remove either one seperately, only when both are removed.
So I removed these two fuses overnight to see if the battery would drain low enough for the battery brain to dissconnect it, and to my suprise it did still drain. So last night I did the same thing but I removed all the blade type fuses that are under the hood and in the morning everything was still connected.
I might be onto something.
12-17-09, 08:50 AM
#7
70-80 milliamps is definitely unacceptable. As far as manufacturer allowances go I believe that Chrysler is the highest at 50ma. GM's allowance is as low as 30ma! 70 -80 is definitely going to have an affect, as you have experienced. I would say that as a general rule anything under 30 is acceptable.
But sounds like you have narrowed the issue though. Now that you know what circuit the draw is on, you can now start disconnecting items within that circuit to see which the culprit is. This is what your mechanics should have done for you. It can be a very tedious task and most of the time is a pain in the a. Get a wiring diagram for the dome lights and the radio circuit and go to town.
I do this sort of thing often at work (for a living). You are well on your way to figuring this out, you've already surpassed the hardest part, knowing how to hook up and read for a draw and knowing to disconnect fuses to isolate the circuit.
keep us posted...hope this helps.
But sounds like you have narrowed the issue though. Now that you know what circuit the draw is on, you can now start disconnecting items within that circuit to see which the culprit is. This is what your mechanics should have done for you. It can be a very tedious task and most of the time is a pain in the a. Get a wiring diagram for the dome lights and the radio circuit and go to town.
I do this sort of thing often at work (for a living). You are well on your way to figuring this out, you've already surpassed the hardest part, knowing how to hook up and read for a draw and knowing to disconnect fuses to isolate the circuit.
keep us posted...hope this helps.
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12-17-09, 11:48 AM
#8
70-80 milliamps is definitely unacceptable. As far as manufacturer allowances go I believe that Chrysler is the highest at 50ma. GM's allowance is as low as 30ma! 70 -80 is definitely going to have an affect, as you have experienced. I would say that as a general rule anything under 30 is acceptable.
But sounds like you have narrowed the issue though. Now that you know what circuit the draw is on, you can now start disconnecting items within that circuit to see which the culprit is. This is what your mechanics should have done for you. It can be a very tedious task and most of the time is a pain in the a. Get a wiring diagram for the dome lights and the radio circuit and go to town.
I do this sort of thing often at work (for a living). You are well on your way to figuring this out, you've already surpassed the hardest part, knowing how to hook up and read for a draw and knowing to disconnect fuses to isolate the circuit.
keep us posted...hope this helps.
But sounds like you have narrowed the issue though. Now that you know what circuit the draw is on, you can now start disconnecting items within that circuit to see which the culprit is. This is what your mechanics should have done for you. It can be a very tedious task and most of the time is a pain in the a. Get a wiring diagram for the dome lights and the radio circuit and go to town.
I do this sort of thing often at work (for a living). You are well on your way to figuring this out, you've already surpassed the hardest part, knowing how to hook up and read for a draw and knowing to disconnect fuses to isolate the circuit.
keep us posted...hope this helps.
And I removed the two fuses in question but the battery was still disconnected overnight soooo......idk
12-17-09, 11:55 AM
#9
I do agree with you regarding the higher amp draws being more likely to have an affect "overnight" but if you've had this for say awhile. You never know how your battery has been affected....have your battery load tested. could have been affecting the battery slowly over time and now the battery's life has sort of caught up with it. just fixed a vehicle yesterday with a similar problem and i was the third mechanic to look at it. It did have a draw from an aftermarket dvd player, but the battery had been so adversely affected that even taking the issue out of the equation the "newer" battery had developed a problem internally and was thus causing more electrical problems thought to have been from a draw.....
12-17-09, 12:24 PM
#10
I do agree with you regarding the higher amp draws being more likely to have an affect "overnight" but if you've had this for say awhile. You never know how your battery has been affected....have your battery load tested. could have been affecting the battery slowly over time and now the battery's life has sort of caught up with it. just fixed a vehicle yesterday with a similar problem and i was the third mechanic to look at it. It did have a draw from an aftermarket dvd player, but the battery had been so adversely affected that even taking the issue out of the equation the "newer" battery had developed a problem internally and was thus causing more electrical problems thought to have been from a draw.....
. But unfortunately, I now know much more than I want to know about this stuff. I had a battery that had been discharged a bunch and sometimes when the battery brain disconnected it, it would need a jump anyways. Therefore, I got a new battery about two months ago and the battery brain has been on it since. It has never been fully discharged.
12-17-09, 02:10 PM
#13
I'm in the Hollywood/Cooper City area.
