I'll throw out a wild guess.

I have a problem with current drain if I use the rear defroster or defogger, perhaps whatever it is relay or switch?) that controls ththis has a problem. Pull the fuse for this and check the drain....

Not sure this helps, but I know I have a problem with this.

 

looks like we are all surfacing like theives in the night now hahaha.

 

Ok, I have started in on it.

Disconnected the starter and everything beyond - no drain. It's not the starter

Connected the starter and alternator and disconnected everything beyond. No drain.

Bypassed the alternator by removing the two red leads and clamped them together. 2.5A drain. Fried Voltmeter number 2. It's not the alternator.

This means it's on to the fuse/relay board where the harness dumps out.

Stay tuned

 

Just a WAG, and probably just pissin in the wind, but there are a couple of things that pull current at all times, although very little and definitely not 2.5 amps. The stereo,clock,electric antenna and the alarm system (if you have one) all have a constant power, whether the key is on or off. If I'm wrong, someone please correct me.

Anthony Tate
79/928 Silver Metallic

 

Anthony,

You are correct. Once this transient 2.5 amp surge dies down (about 5 seconds) my radio beeps through an initialization which draws 250ma for about 3 seconds, and then everything drops down to about 50ma at steady state which would be the stuff you mentioned.

The alternator connection out dumps onto bus 30. I just cataloged all the connections and will crash through them tomorrow. Many of them can be taken out of the circuit by a fuse or a relay. There are 3 that can't so I will likely be pulling plugs to pick them off.

Here is the list

Not fused and no relay

Circuit Fuse Relay Comments
A2 none none Ignition switch
A2 none none Light switch
A1 none none Ignition switch
A1 none none Dimmer switch
E7 none none Emerg flasher switch

Things that can be taken out of circuit by removing a fuse

Circuit Fuse Relay Comments
14 none Power seats
15 XI Radio, rear wiper
16 XVIII Cooling fan relay
17 XXI-XXII Fresh air blower
18 I-II Rear window defog
19 XIX/XX Headlight relay
20 VII Headlight washers
21 VI Power windows
22 none Fuel Pump
23 Interior lights

Things that can be taken out of circuit by removing a relay

Circuit Fuse Relay Comments
E7 none X Two tone horn
87 XII Fog light relay
30 none XIX/XX Headlight relay

May not be connected to anything
Point k8 none none
Point Z3 none none

Anyone want to place a bet on any of these?

 

And the winner is?
I'd try the interior light circuts.
Last year or the year before we had a rash of posts where the door, map, and rear compartment lights were miswired. Should only be 2-3 three bayonet type leads per unit. If they are wired wrong -PO or a clean-up gone bad- that 3 way rocker switch -always on, always off, or on only when that door is open when the door pin switch is released could probably cause you this grief.
Also since the door pin switch also activates those little red marker puppies as well as the interior lights you have multiple possibilities for pain. Which reminds me............. .
Check to see if all pin switch related lights are working, including those little red door marker lights, check the pin switch as well.
You haven't been tinkering with the windows or door speakers recently, have you?
Finally, opening and closing doors seem to eventually find a way of bending a wire or two back and forth wether they are in a conduit or not-it'll get them on either end-. Years ago it was a problem on big luxury sleds out of Detroit, not so common now.
Come to think of it these lights and switches operate key off...hmmm...

 

"Why do you keep doing that painful stuff?"
"Because it feels good when I stop."

Mystery solved!
The answer: The circuit off of fuse 15. The hot wire which goes to the rear wiper was (barely - 1.5 MOhms) shorting to ground somewhere in the harness along the passengers side.

The fix: run a new wire following the existing harness.

Current drain now starts at 50ma, cycles up to 250ma while the radio reboots, and then settles down to 20-30ma.

Tip: Remember to shut the door when checking the circuits. The open door will draw 2+ amps and simulate the original failure.

Thanks for the advice and pointers.

 

Dude you are THE MAN!!!! Thanks a million I will check mine and replace it if neccessary!!! YOU ARE THE MAN!!

 

Does the rear wiper work?

 

It does. But you made me go check :-)

 

Mark,
I've whined about my fuse blowing brakelight/markerlight problem for about a year now and pledged to rewire as you have done.
I even bought spools of various colored wire,soldering gun, connectors, and and shrink tube.
You have shamed me into doing the obvious.
Thanks...I think?
I was going to sneak down to Corpus today with my son to check out Senor Tate's 'Third Shore' sHARk, but lights do take precedence.
BANZAI !!!

 

John,

Good luck with it. The routing along the back seat and the back panel managed to elicit a few choice words. I am really curious as to where in that harness the short is. There are lots of places that are possible pinch points. As it passes the bottom corner of the door, if one was careless, they could run a trim screw right into the middle of it! I didn't see any damage to the outer sheath as I traced the harness. If you find anything that looks suspect I'd be interested to hear.

Cheers,

 

Hat's off Marc!!

I've got a drain problem on my car and you have very nicely detailed why I just throw a battery charger on the car when I'm not going to be driving it for a few days. I also have one of those solar battery tenders that helps, but it doesn't seem to work too well with the car cover on!

I'll have to bite the bullet sooner or later and hopefully wont fry my new Fluke Multimeter.