5.0 battery drain November 30, 2005, 09:31:45 PM I have a 88 couger and it has a major battery drain. One morning when I tried to start it the battery was about dead. Just like that. I test between the battery and -cable and it reads over 5amps. The battery is good. When I hook the battery cable up there is big time sparks. I pulled all the fuses,breakers that could be pulled on the fuse block and there was still a draw.I pulled the starter wire of the solenoid. No change there. Every wire that goes to the main hot terminal drew the same amout of amps on the gauge.But only the yellow wires eyelet would arc.Even my stereo amp ,which is wired fine will do the same thing, draw the 5 amps. When I pull the main fuse for that the draw goes away. Basicly Any wire that is hooked up to a circut ,will draw that 5 amps. I have unplugged the alternater harnesses , and other big ones under the hood. Nothing changes it. Is it the computer? I need Help!! Thanks, Tony Quote Selected
5.0 battery drain Reply #1 – November 30, 2005, 10:02:16 PM try letting the car sit over night with the battery unhooked too see if it goes dead. I know your already using a more sophistacated(sp?) means of testing your problem but start at the basics. Quote Selected
5.0 battery drain Reply #2 – December 01, 2005, 09:44:45 AM Quote from: y89tata Every wire that goes to the main hot terminal drew the same amout of amps on the gauge.But only the yellow wires eyelet would arc.Its not very likely they all are drawing 5 amps...I'd concentrate on the yellow wire makin the sparks... Looking at the wiring diagrams, it's possible to have a bad rear window defogger controller that is staying on continually. Never seen it happen but there is always a first... Does you car have the automatic temp controll or manual lever heater/AC(it makes a difference on component location)??? FYI if that is the problem, the glass should be warm... You can always check to see if there is voltage on the two terminals at the glass.. Quote Selected
5.0 battery drain Reply #3 – December 01, 2005, 10:36:54 AM Maybe a stuck ignition switch too... Quote Selected
5.0 battery drain Reply #4 – December 02, 2005, 09:35:44 PM I found the #8 fuse is the one that is draining. If I unplug the fuse the battery stays up, and started fine at 5 cold degrees above this morning ,when I got up. It runs the power locks,digital speedo,interior lights ,(exept the two in the back), The memory on the radio and digital clock. Its not the power locks, I unpluged that relay and theres no draw, and the radio is fine. Interior lights go off after 30 seconds or so when the doors close. What I overlooked was the floor on the drivers side gets wet on the floor and in the back on the floor when it rains. I don't know where that leak is. Its not any of the door weatherstrip. It comes down the firewall from the windsheild or cowl. Anyway, that water sits in there if I don't suck it out. We got rain and ice on monday untill it changed to snow that night, so there's 1" of ice back there. I'm thinking if there is any wires that run threw there with any sort of connection,the water could be shorting out the wires, Just a thought. I do not know if any wires run along side the the sill plate or rocker panels by the floor?? I'm running a switch to the #8 fuse spot for know so I have a speedo and radio. I just have to remember to shut it off when I turn the car off. Thanks for helping Quote Selected
5.0 battery drain Reply #5 – December 03, 2005, 05:22:15 AM QuoteIts not any of the door weatherstrip. It comes down the firewall from the windsheild or cowl.i was pulling my hair out on this one as well. i think ive got her licked though. the junction between the firewall, front fender and door area is a little questionable. i (poofed) baby powder all over the inside under the ferewall ets after i dried it out good (after removing the carpet). it rained the next day and where it was leaking left a trail...i still havnt taken the fenders off but the broblem seems to be coming from that a way. pull your carpests out and dry them. it will take eayons if you dont remove the insulation. its amazing the differance in weight once its dry and stripped... try the baby powder thing...worked well for me. i suppose chalk would work as well but it might be nastier to clean up. QuoteI'm thinking if there is any wires that run threw there with any sort of connection,the water could be shorting out the wires, Just a thought. I do not know if any wires run along side the the sill plate or rocker panels by the floor?? theres a ton of them. the front and rear floors arent as sepperated as i thought as wel. the hump between the 2 still has a gap under it and water will get by and collect in the back. hope this helps out some... Quote Selected
5.0 battery drain Reply #6 – December 03, 2005, 12:11:19 PM Hey there,As far as the leak I had the same thing. It was leaking past the grommet for the hood release cable. Sealed it up with silicone.Also had a similar thing with the battery drain. But mine was the alternator and if you already disconnected it guess that's not it.Good luck,Bob Quote Selected
1988 Thunderbird Sport, Former 4.6 DOHC T56 conversion project. 
Topic: 5.0 battery drain (Read 1048 times)
previous topic - next topic
