Rohn

Maybe someone can comment?

I have had a short past three years where if car not driven for 3 days it will not start.

It has to be a circuit that has power with key off.

I recall someone saying rear hatch lid latch is most common.
If not latch then light switch would cause the interior light to be on so cant be that.

I also hear the motors for headlight may be sticking on. But that would kill battery much sooner. Right? I would hear that.

Also i recall the power seat is a culprit?

Is the procedure to pull circuit fuses and watch the amp draw drop? What is normal amp draw one would expect?

If fuse, that serves numerous switches etc. how to discern which one? Is there a procedure?

TY.

steven mack

Disconnect your negative battery cable.Then connect a test light between battery cable and ground.If you have a short the test light will come on.Now pull one fuse at a time and watch the light.When the light goes out after you pull a fuse that is the circuit that has the short.

Rohn

Thank you. I do have a test light. I also have a multi meter. What amp draw is "normal" for a car without issues?

ccrazor

IIRC GM says max. of 50 ma..

jfb

If you had a short, you would blow a fuse, a fuseable link, or trip a circuit breaker. The only circuit that is not fused is the starter motor. You have excessive leakage current. GM does say leakage current should not exceed 50 milliamps. My 87 draws 27 ma and I have no battery problems. Removing the neg batt cable and place an ammeter between neg batt post and cable to allow you to measure leakage current and pull fuses one at a time while you watch the ammeter. Pull the courtesy light fuse and keep the hood down because the courtesy lights and underhood lights draw 1-3 amps. To protect your meter, start out at 10 amps and if you have too small leakage to see on the 10 amp scale, then change your meter to lower full scale amps. Most meters require unplugging the positive probe and plugging it into a 10 amp socket.
Do not leave your key in the ignition because this keeps the antitheft circuit on and discharges the battery. At night check for underhood lights, vanity mirror lights, console light, rearview mirror map lights, door map lights. Do you have a CB, radar detector, GPS, aftermarket alarm or radio or audio amplifier, if so, check em.
Also, don't let your battery sit there doing nothing because even disconnected, lead acid batteries self discharge and car batteries are ruined by repeated deep discharging. Get a battery tender and keep the battery charged up when the car is not in frequent use.

ddahlgren

I fixed 99% of all electrical problems I had initially by disconnecting and removeing the aftermarket remote start / alarm system the original owner had installed in 91. If you have one it is a suspect right off the bat.
Dave

rrt898

Mine was the fusable links behind the battery.

jtc44

This trick has helped me. Get a battery disconect switch from parts stor the ones with a knife switch on it now put it on the neg. side of bat. run car for a bit then take the key out now you can use your DVOM to test for a draw start with 10 amp scale and work down the great part of using a switch is you can open or close it to change your meter leads or open the door with out risk to your DVOM

steven mack

Where can I get replacement fusible links?I couldn't find the right kind So I replaced the burnt one with a inline 20 amp fuse to replace the 20 amp fusible link.Will this cause a problem?

ddahlgren

NAPA should list them..

ch@0s

the most common short usually occurs once the driver make contact with both the steering wheel and the shifter.

GREGGPENN

My problem (in this regard) ended up being a faulty/intermittent door jam switch that let the interior (courtesy) lights go on/off.

As far as the most common short...
I think that would be a .22 short.

Ramjet