Don't kill me because i don't own a 3rd gen....someday.
I have a 1979 K5 i converted to tbi years ago....great running
truck but i have a small issue and i'm in need of a spec.

She's been sitting for a couple of years and i'm currently going thru her to be my DD again but this time it'll be oil feild duty.
So we are going with cross over steering...air lockers and such.
While sitting in the back yard the last year or so i noticed the battery would allways go dead so i finally have her in the garage so started doing a parasitic draw test. I had a .24ma draw. Found if i unplugged the altenator or ecm with the entire fuse panel emptied i could get rid of the draw. I installed a late model alt used on all serp belt (88) up trucks and lost the .22ma draw with the alt plugged in. So i plugged the ecm backin and i have a .16ma draw. I have several test 7747 ecm i keep around since i converted my other k5 to tbi also and get the same problem. GM says anything over .050 ma is bad....so i have .16ma with the ecm hooked up. That being said i still need to remove the starter from the equation and run the ecm battery hot wire directly from the batt to rule out a poss autozone rebuild issue. But i'd like to have a spec on how many ma's a ecm draws with the key off.

Anybody have an answer?

Doug W.

 

Not positive, but i would say look somewhere else.

1 amp = 1000 ma, so .16 ma would be a real small current draw. Look at it like this. Most small LED's pull at most 30 ma. And will run off of a AA battery for a LONG time.

Have you tried another battery?

What did you measure this with? Just curious.

Unless I totally misread the post.

 

Ask on the DIY board of hopefully a mod will read this and move it. I know you'll get an answer there.

 

Read it.........and moved it

 

I use a fluke 88 meter across the negative side of the battery.
Half the problem was in the altenator. I carry a spare 10SI in the truck so i plugged it in and the 00.22 draw became a 00.16 draw with the ecm hooked up. However i need to remove the main feed to the starter and see what the ecm draws when it alone is the sole consumer. Which will to wait as i had to head to work unexpected last night which required driving thru the night to wyoming to an oil rig....never fails...and i was so close.


Doug W.

 

According to the '92 Camaro Helm manual the maximum allowed parasitic current draw is 25 mA (p. 6D1-4 battery).

The ECM can draw up to 10 mA during key-off and be OK (p. 6D1-6 battery).

I think that you have the decimal points in the wrong location. A .24 ma draw (from the first post) is only 240 micro-amps, well within spec. If it is a decimal point issue, and the actual draw is 16 or 22 mA (from post above this one) then all is OK.

RBob.

 

Rbob...i think the decimal point is getting me also.
Like i said...fluke 88. MA red lead...com black lead.
If you press the range button to manually set the
range you cycle between ma and amps. My 76 K5
with tbi reads .036ma across the negative side.
Research on the net stated gm's current spec is .050.
My 79 i am working on reads .16ma. Between the ecm
draw and the altenator the draw was the same .22ma.
Taking one draw away made the reading stay the same
like adding two resisters together and cutting the total
resistance in half. Strange but true. I am assuming that
the meter reading of 00.22 is actually 220ma..because
anything the the left of the decimal point would be reading
amps and anything to the right of the decimal point is ma.
So a .036 is 36 ma which is well within the gm .050 spec
and making the current .16 ma reading 160 ma if i am
on the right track.

Also i will be spending the next several days reading from the
top the entire prom editing section as that is what i want to learn
next. Could you recommend anyone on the board who would
be willing to tutor me in the right direction. I understand the basic
tools needed to do but i'm interested in the prominator that saves countless hours. Then i figure the next step is to make a basic math table to get all the needed specs to work with...ie: 350 needs x lb fuel injector etc.

Doug W.