Electrical Quandary

[Nomake Wan]

Since things have somewhat come to a head lately, I figured I'd do a full update on the electrical gremlins plaguing my SVX.

First off, the battery and alternator are perfectly fine. I've checked and re-checked them and they are fine. However, if the car sits for a while (week or more) then the battery discharges. Something's drawing. I don't know what, though. It's not the power seatbelts, they work fine and I don't get the trademark clicking sound from the computer. I'm not sure what exactly is drawing.

But then today I did a full checkup on what works in the cabin and what does not.

What works:
Wipers, Climate Control, headlights, foglights, parking lights, brake lights, clock, cigarette lighter, lights in dashboard gear indicator, light on window switch, lights in climate control buttons, temperature selector lights, "on" light on cruise control, "on" light on foglights, hazard lights, turn signals, dome light, ignition light, dash warning lights, door key light, door lights, air conditioning, cruise control.

What doesn't:
"on" light on defrosters (side mirror/rear window), "on" light on parking light, "on" light on security switch, security switch, sun visor lights, instrument panel backlights, backlights for every single switch (what lights up the text on every single panel including the center console and gearshift)

I have not yet checked the wiring on the cigarette lighter or sun visors, but I suspect the sun visors most. They droop and I have a feeling they were never checked.

Just today, though, I noticed some peculiar activity. If I turn on a turn signal, all the lights in the car dim (except the clock) whenever the turn signal is on, then return to normal once the signal is off, then dim again for the next "on" in the cycle. However, if you turn on the hazard lights, this dim still happens... but it's not nearly as profound. I would think that having both sets of blinkers on would draw more power, but apparently not.

I then noticed while sitting in a drive through that my clock had gone out. I still had a response from the cigarette lighter and climate control though. When I popped the hood I found that the 10A fuse in the main fuse box for the clock was blown. Now, I had just replaced this fuse two weeks earlier (with all the other fuses) because the ones that were in the boxes were the wrong ratings.

The car is (hopefully) going under the knife today electrically, getting all of the wiring behind the dashboard inspected. There are remnants of an aftermarket security system in the car, so I highly suspect that it was not installed properly and is causing most of the problems. However, murphy's law states that removing these foreign elements will not solve the overall problem. Does anyone recognize my symptoms? If so, please help!!

[ItsPeteReally]

Originally Posted by Nomake Wan

However, if the car sits for a while (week or more) then the battery discharges. Something's drawing. I don't know what, though. It's not the power seatbelts, they work fine and I don't get the trademark clicking sound from the computer. I'm not sure what exactly is drawing.

It doesn't have to be much, there's a 168 hours in a week, so a 200-300 mA drain will flatten your battery in about that amount of time. To narrow down the search put an ammeter in series with the negative terminal lead from the battery and the battery post. Hopefully you will see a significant current drain. If you do, pull the fuses one by one until the drain goes away (or at least seriously reduces) if you are lucky you will find one massive source of leakage and not 5 smaller ones!

Originally Posted by Nomake Wan

Just today, though, I noticed some peculiar activity. If I turn on a turn signal, all the lights in the car dim (except the clock) whenever the turn signal is on, then return to normal once the signal is off, then dim again for the next "on" in the cycle. However, if you turn on the hazard lights, this dim still happens... but it's not nearly as profound. I would think that having both sets of blinkers on would draw more power, but apparently not.

There would appear to be a high resistance somewhere causing a voltage drop, possibly in the indicator switch itself or associated wiring, but the hazard warning system and the indicators do use separate fuses, so the problem could just be a poor contact at the fuse. Use a meter on the volts range to find where the voltage drop is occurring.

Originally Posted by Nomake Wan

I then noticed while sitting in a drive through that my clock had gone out. I still had a response from the cigarette lighter and climate control though. When I popped the hood I found that the 10A fuse in the main fuse box for the clock was blown.

That's definitely wrong. No clock takes over 10 amps! But seeing as the clock circuit is powered all the time, I'd suspect that the aftermarket security system tapped into this supply and the additional redundant wiring is occasionally shorting out somewhere.

[Nomake Wan]

You should've seen what the wiring looked like before I had a go at the fuse boxes. Someone had removed the cover to the fuse box in the cabin so they could splice wires DIRECTLY into some fuses. I didn't note which fuses were being abused, I just yanked the wires out and replaced the fuses with new ones. This whole car has been something of a nightmare.

I'll do the meter test. I, too, hope that it'll be one massive short and not a bunch of small drains. Thanks for the response!!

[Nomake Wan]

Well, I was right.

Getting rid of all the trashy wiring didn't solve the draw or short problems. In any event, the mess is gone and the radio cage is in. It doesn't fit. Oh well. I'll have to take a careful look at what exactly is causing my problems.

I have this sinking feeling that whatever it is that's shorting out has also blown all the bulbs that don't light, and the security module...

[ensteele]

Which bulbs don't light? Could they have just burned out?

[Nomake Wan]

It is a LOT of bulbs, ensteele. A lot.

ALL of the backlights do not work. This includes the instrument panel, and every single button on the dashboard and center console.

The only lights that DO work are most of the "ON" lights in the switches, the warning lights on the dash and the gear indicator light in the instrument panel.