Computer Current Draw with Car Off

[Steve Wood]

Yep, that sounds like the winning idea.

Now, for clarification, do you have a Buick transplant, or is this another car with a problem.  No need for me to disconnect a buick to check for current draw if this is a ford pcm. 

This is not an excessive amperage draw for some cars and a good battery should be good for at least a month

[Dont Panic]

It is the buick transplant, buick computer and a homemade stand alone GN wiring harness that was put together following the GN wiring diagrams.  If you can check your current draw that would be awesome.  How would you check it, with and without the ECM fuse connected?

[Steve Wood]

ammeter between negative post and cable

[Just a Six?]

Devon I should also have a spare ECM if the time comes you need one to try one for testing.
Your gonna be buying the first round when we go for a beer tho!! 

[Dont Panic]

I know I have a spare or two myself.  Probably 3 ecm`s in total.  I used to pick them up at the scrap yards back in the day.  I sent them off to storage last week though (2.5 hour drive away).  I am pretty sure it is not an ecm problem as I have run the car with multiple ecms and the battery has always drained.  Dave, thanks for the parts offer again, you have been a big help!

Steve,
I think I would need two readings for a comparison.  One with everything connected, and one with the ecm fuse disconnected.  This would give me a better idea of the draw from the GN engine harness / ECM combo (1st reading minus the 2nd).

[Steve Wood]

I am 70 years old and don't crawl in floor boards to unplug fuses unless I absolutely have to! 

[Steve Wood]

Starts at 140 ma and drops to about 6 ma in a few seconds...gues sing that is radio and ecm.

My advice is to leave the battery disconnected and put a battery tender or one of the more modern units on it to keep it from going bad.

You can unplug the the orange memory wire if you want to separate the ecm from the rest.  The ecm-ign fuse is separated from the battery by the ignition switch.

[SuperSix]

http://www.harborfreight.com/automatic-battery-float-charger-42292.html

[Steve Wood]

I prefer the ctek over the battery tender but both will do a good job and I have both of them.  The main thing is to not use one that puts out a continuous charge as these can damage a battery over a long period of time. 

[daveismissing]

on sale Devon:

http://www.canadiantire.ca/AST/browse/4/Auto/BatteryChargersAccessories/BatteryChargers/PRD~0111522P/CTEK%2BMulti-use%2B3300%2B3.3A%2BBattery%2BCharger.jsp


I use two.
Dave