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You plug it in to your OBD terminal. You will have to find a way to mount it. I actually used an old phone mount which I modified, will take a picture and post...good luck.
I have a 2004 SC430 with the same battery drain problem. I systematically went through my fuses measuring battery current after each fuse was pulled. You have to shut the doors and wait about 10-15 minutes for the current draw to reach a minimal state with all the computers and floor lights to shut down. The car was draining 150 mA from my battery when not being used. After much time and effort, it turns out that the telephone computer (fuse located under the hood) was pulling 100mA. With that fuse out, the current draw dropped to 50 mA, which is still not great but much better. Since no other systems seemed to be affected, I just left that fuse out. Still use a battery tender when not using the car for several days, but hopefully this latest battery won't die within a year.
I have a 2004 SC430 with the same battery drain problem. I systematically went through my fuses measuring battery current after each fuse was pulled. You have to shut the doors and wait about 10-15 minutes for the current draw to reach a minimal state with all the computers and floor lights to shut down. The car was draining 150 mA from my battery when not being used. After much time and effort, it turns out that the telephone computer (fuse located under the hood) was pulling 100mA. With that fuse out, the current draw dropped to 50 mA, which is still not great but much better. Since no other systems seemed to be affected, I just left that fuse out. Still use a battery tender when not using the car for several days, but hopefully this latest battery won't die within a year.
I don't have much to add to this thread except my short experience with my SC. I bought it in October and previous owner said he would keep a tender on it too. I don't have a tender yet but have left the car untouched for up to 3 weeks with zero starting problems. He did advise me to make sure I remove the key from the ignition because he thought/read that may be one of the draws??? I also just close the door on the car since it's in my garage so does that keep the alarm off or is the car smart enough to arm itself??
RJS, if you just close the door after you got out the car, the alarm will not arm, however, if you arm the car, then disarm it, open the door then close the door, it will arm itself.
All of our cars got fitted with external jacks for their battery tenders. A little triangular flag on each plug acts as visual reminder to unplug, but it's really become habit.
Arrive home, plug in.
Unplug and cap the jack before leaving. Just seconds, no more surprise dead batteries, and battery gets reconditioned every time.
I just bought a 2004 SC-4 30 with 25,000 miles on it. Suddenly one day the battery was dead, I mean 2V dead. It happened suddenly. I just took the car in for the air bag replacement. When I picked up the car at the dealer they had to jump it. When it died the first time I charged the battery for a day and a half and it worked fine for a couple weeks before the dealer jump. I am convinced that something intermittently drains the battery. I am going to replace the battery cables because they are corroded and the + cable won't tighten. Would appreciate if someone has found an intermittent hard drain of the battery. Put an ammeter on the battery and found no current drain when the car is shut off. Heard something about the audio power amp.
Johnsonmcc, there are multiple potential power drains in this car. Having said that, this car is hard on batteries, so be sure to have a load test run on your battery as it may be ready to be replaced. Batteries don't tend to last very long in the SC430, though there are a couple of battery technologies that do perform better. (There are a couple of threads about that on this forum.)
Potential drains:
Leaving your lights on automatic (strong suspicion, though not confirmed through measurement yet on this forum)
Arming your security system (strong suspicion, though not confirmed through measurement yet on this forum)
An interior light left on, including the trunk light (change all your interior lights to LEDs to reduce that drain by 90%)
The phone ECU (see post # 80 in this thread)
You can test for other drains (see post # 72 in this thread)
However, a big problem is what you stated and that isn't a drain but a cable problem. With corroded cables and connectors, the alternator can't recharge the battery and the battery can't supply power out to the car. So I'd recommend that you start with either replacing those cables or at least re-terminating the cables with new connectors. Then clean up your battery terminals and put some battery terminal anti-corrosion treatment on them. Then see if your battery still goes dead. (But still do a load test on it.)
01-29-20, 04:15 PM
