Truck help needed again

[Daplumma]

I posted a couple of weeks ago about my truck battery going flat after sitting a couple of days.The 4wd service light was on and the selector motor was drawing current with the truck off and key out.It also was not shifting into 4wd.I replaced the motor and now it goes in all of the gears but the motor is still drawing current and killing my battery.When I disconnect the battery I can hear the selector motor click.The motor is also warm to the touch when the truck is sitting.I'm happy to have 4wd again but I need to sort this battery draw out before I can trust this thing.The truck is a 1999 GMC Suburban.Its a late in the year 1999 and the selector motor was the same as a 2000.Thanx in advance.

Joe

Edited June 13, 2009 by Daplumma

[ecmilley]

check for a sticking relay in the power box under the hood (I"ll look up a diagram for ya and repost)

[Daplumma]

Thanx

[ecmilley]

there doesn't appear to be any relays to stick in the system which would lead us to either shorted out wiring or a bad transfercase control module,or a bad dash selector switch the large red and black wires on the encoder should only have voltage when they are switching ranges, no pwer with the key off.

lt green wire in E conn in encode is 8vts.

first thing two fuses a 15amp 4wd fuse and a atc 20 amp fuse pull each one and see if there is still power going to the encoder .

if you pull the atc fuse and it clears up pull unhook the selector switch in dash and put fuse back in if it isn't making a draw you most likely need the switch if not the atc.

also try wiggling the harness gently to see if you get ang problems under the truck.

 

i have replaced a couple modules for similar issues this year but it does sound like the transfercase module is sticking

[Daplumma]

If I pull the 20a fuse to the tcase it de-energizes the motor.I'll mess with the switch later.Thanx again.

Joe