I did some test and came up with this . I unhooked the negative battery terminal and hook a test light to the battery and touched the core support , it lights up so this tells me I have a drain. I start pulling wires off the hot side of the starter relay , the lght goes out when I pull the yellow wire that turns into 4 wires . I hook this wire straight to the battery and light comes on ,as I get into the car to start looking the open door chime starts dinging . While it is dinging ( battery ground wire still unhooked ) the test light flashes the exact same time it dings every time . I unplug the plug at the steering column the light goes out a little more but the door chime is still dinging it keeps going until I take the key out of ignition. What the hell is going on ??
battery drain problem
- Thread starter 1slo8850
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Your test instructions sound a little odd to me. Here is the correct proceedure...
The ideal method is to disconnect the negative terminal, and connect a Digital Multimeter (DVM) between the negative terminal on the battery and the negative cable. Set the DVM on a low current scale of 2-5 amps if it doesn't auto range. Watch the current draw, and then start pulling out fuses. When you see a sudden drop in the current, that circuit is the likely culprit. Note that the computer, radio & clock will draw less than 1/10 amp to keep the settings alive.
Using the negative side prevents nasty accidents like shorting the wrench to ground while disconnecting the battery cable. Electrically, the test will work with either positive or negative battery cable.
Small things like glove box or courtesy lights are often the culprits. If you have an aftermarket stereo or alarm system, it is also suspect.
The ideal method is to disconnect the negative terminal, and connect a Digital Multimeter (DVM) between the negative terminal on the battery and the negative cable. Set the DVM on a low current scale of 2-5 amps if it doesn't auto range. Watch the current draw, and then start pulling out fuses. When you see a sudden drop in the current, that circuit is the likely culprit. Note that the computer, radio & clock will draw less than 1/10 amp to keep the settings alive.
Using the negative side prevents nasty accidents like shorting the wrench to ground while disconnecting the battery cable. Electrically, the test will work with either positive or negative battery cable.
Small things like glove box or courtesy lights are often the culprits. If you have an aftermarket stereo or alarm system, it is also suspect.
Now you have to continue the test while dissecting the yellow wire's circuit. I dont think you listed a year of Mustang but if it's an '88, the following diagram might help. The yellow wire is a distribution leg for many circuits. Start disconnecting those circuit legs and note when the draw diminishes.
Schematic
Schematic
Ok checked the wires pulled no.1 fuse nothing, pulled no.4 fuse nothing, unhooked relay at fuel pump nothing, onhooked rear defroster nothing . Are these the right wires ,these are the ones I determined from the schematic. After unhooking each wire I hooked it back up and moved to the next one. Now what do I do
Did you disconnect the ignition switch's electrical connector? With the issues the ignition switches have, it could be the source of an issue.
This article shows how to replace a switch, but I figured it would help with accessing the switch. If you have the *slightest* doubts about yours, replace it. They're about 20 bucks from the dealer and 1/2 to 2/3 that much at the parts store (I used Ford parts on mine).
You can also get a replacement electrical connector if yours is burned up.
Otherwise, it seems like you could be looking at an issue with something else tapped into one of those circuits (an aftermarket item or non-factory wiring), or there's a possible issue with the wiring but it's not a dead short.
You did disconnect the wiring to the alternator during your testing, right? More than one amp is a decent draw. If a reg loses a diode, it can create a draw. It was worth confirming...........
Good luck.
This article shows how to replace a switch, but I figured it would help with accessing the switch. If you have the *slightest* doubts about yours, replace it. They're about 20 bucks from the dealer and 1/2 to 2/3 that much at the parts store (I used Ford parts on mine).
You can also get a replacement electrical connector if yours is burned up.
Otherwise, it seems like you could be looking at an issue with something else tapped into one of those circuits (an aftermarket item or non-factory wiring), or there's a possible issue with the wiring but it's not a dead short.
You did disconnect the wiring to the alternator during your testing, right? More than one amp is a decent draw. If a reg loses a diode, it can create a draw. It was worth confirming...........
Good luck.
I did disconnect the switch at the ignition and there was no change, I'm replacing it though 20 yrs old , not taking a chance.
The only wire hooked up to the alt is the charge wire ( 3G setup) but I didnt un hook it.thefactory ones are just tied up to the side.
The car didnt run when I got it, I kind of started from scratch so I dont know what the previous owner did but I have looked pretty good at the harness through out and can't see any splices.
The only wire hooked up to the alt is the charge wire ( 3G setup) but I didnt un hook it.thefactory ones are just tied up to the side.
The car didnt run when I got it, I kind of started from scratch so I dont know what the previous owner did but I have looked pretty good at the harness through out and can't see any splices.
After I hooked up the new switch and found now change I hooked up meter , shut door, and started pulling fuses . Narrowed it down to #8 which I went farther and found out it is the acc. power wire for the radio, but according to my diagrahm goes to the #11. that makes no sense. Next I found the power wire to my guage as a little drain, does that mean I have a bad guage.
8 might be memory power for the radio. How much did the meter drop?
Your aftermarket gauges should be wired to accessory power, not constant power sources.
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