bladenbullet
Full Access Member
Interesting situation recently...
had an intermittent "no electrical power" situation in the vehicle and traced it to the battery cable swages....instead of adding new cable ends or cable replacement I sweated all the cable end terminal connections with solder and decreased a .4 volt drop at the positive cable to hundredths of a volt...good solid connections...
2 days later I woke up to a dead battery out of the blue...interestingly enough I had just replaced the aftermarket battery (days before the incident) with a new ac/delco 770 cca battery as a precaution just to protect us as the aftermarket age was uncertain (purchased the vehicle used just over 2 months ago)...
the battery was severely discharged and holding at 3 volts when I checked it....I had done previous checks with a midtronics tester on installation and only found the battery was slightly discharged as purchased and a charger brought it up to full steam...I instruct automotive technology at a local tech center so the equipment is at my disposal....
I spent the weekend checking and double checking for a parasitic draw....the battery was disconnected with an ammeter connected so as not to disrupt battery power to any components...I could watch the modules power down and the draw settle in the 22mv range....well within acceptable expectations....
today I hooked up a shunt to operate the vehicle, connect a meter, then break the connection so I could monitor the draw more closely....as expected the draw steps down from an initial 7 amps to 3 then further steps to the 22mv range....I monitored it over a 4 hour period once it reached its bottom point with a fluke 87 set on min/max....I found the draw fluctuates pretty consistently and can be watched running from about 20mv-30mv while monitoring....the min/max capture showed peaks of up to 60ma with dips to 12 and an average of 19mv for the duration of the test....
i'm looking for a gm technician who might verify this fluctuation as normal or not....I know a lot is going on with antitheft engaged and other potential monitoring systems....I just need to know if I should be expecting a steady draw or if the fluctuation is normal for these vehicles...although the average is well within acceptable standards, the variations are unusual from what I am used to during a parasitic draw test....
the vehicle has been fine with no discharge for the past 2 days....I don't know if I caught a fluke or if I may have purchased a battery with an issue....I will continue testing all week with the shunt installed and am currently running a min/max capture for the past 3 hours with similar results....
i'm more curious than anything else at this point....
thanks in advance...
had an intermittent "no electrical power" situation in the vehicle and traced it to the battery cable swages....instead of adding new cable ends or cable replacement I sweated all the cable end terminal connections with solder and decreased a .4 volt drop at the positive cable to hundredths of a volt...good solid connections...
2 days later I woke up to a dead battery out of the blue...interestingly enough I had just replaced the aftermarket battery (days before the incident) with a new ac/delco 770 cca battery as a precaution just to protect us as the aftermarket age was uncertain (purchased the vehicle used just over 2 months ago)...
the battery was severely discharged and holding at 3 volts when I checked it....I had done previous checks with a midtronics tester on installation and only found the battery was slightly discharged as purchased and a charger brought it up to full steam...I instruct automotive technology at a local tech center so the equipment is at my disposal....
I spent the weekend checking and double checking for a parasitic draw....the battery was disconnected with an ammeter connected so as not to disrupt battery power to any components...I could watch the modules power down and the draw settle in the 22mv range....well within acceptable expectations....
today I hooked up a shunt to operate the vehicle, connect a meter, then break the connection so I could monitor the draw more closely....as expected the draw steps down from an initial 7 amps to 3 then further steps to the 22mv range....I monitored it over a 4 hour period once it reached its bottom point with a fluke 87 set on min/max....I found the draw fluctuates pretty consistently and can be watched running from about 20mv-30mv while monitoring....the min/max capture showed peaks of up to 60ma with dips to 12 and an average of 19mv for the duration of the test....
i'm looking for a gm technician who might verify this fluctuation as normal or not....I know a lot is going on with antitheft engaged and other potential monitoring systems....I just need to know if I should be expecting a steady draw or if the fluctuation is normal for these vehicles...although the average is well within acceptable standards, the variations are unusual from what I am used to during a parasitic draw test....
the vehicle has been fine with no discharge for the past 2 days....I don't know if I caught a fluke or if I may have purchased a battery with an issue....I will continue testing all week with the shunt installed and am currently running a min/max capture for the past 3 hours with similar results....
i'm more curious than anything else at this point....
thanks in advance...
