Hello everyone!
2003 Blazer cluster question.
Well I went through the forum and found only one unanswered thread with my issue.
My battery was going dead after a couple days of sitting, so I did the following;
Inserted ammeter into battery circuit
Initially current draw was 105ma
after 15 seconds noticed gauges in cluster appeared to power ( they moved from the rest position to mid scale) fuel and temp
the current draw also dropped to 96ma
If I opened the door or inserted the key I saw the draw increase again to 105ma and then return to 96ma after the 15 sec.
I pulled fuses and all kinds of checks to determine the issue. BCM (TBM) fuse would stop the draw.
Today I let the truck sit about 2 minutes and the current draw dropped from 96ma down to a reasonable 10ma.
Can some one shed some light on what is going on with this series of events?
I'm thinking it has to do with the security system or the courtesy light system.
I will check my battery in a day to see if its down again.
I did have the battery checked for a dead cell, it's good.
Thanks for the info!!
Zlrig

 

Sounds like normal Retained Accessory Power shutting off.


The only way to test a modern sealed battery is to load test it.
1) It HAS to be put on a charger for extended time and slow charged to ensure it is fully charged (can't rush this).
2) You apply 300A load for 15 sec to take off the surface charge
3) You apply the test load for that particular battery for an additional 15 seconds and the voltage needs to still be above a specified amount at the end of the test.


I have seen very few load testers still out there.

This is one of the times of the year when batteries go bad. Since you have already checked for a draw I would make sure vehicle is charging well and if so go ahead and replace the battery. Only takes one time being stranded to pay for it.

 

Lesmyer, thanks for the reply!

originally I installed a new after market radio and it had an issue staying on for some reason.
Not knowing how the trucks electrical system was setup, set me up!
It is odd how the temp and fuel indicators go to the mid point of the scale when power is off.
That screwed me up and led me down the wrong path when I had actually corrected the radio problem earlier.
I personally like older vehicles with none of this high tech crap. Much easier to work on and less to go wrong!
Thanks again for your input!
JB