M1123 parasitic draw. Solenoid?

[Thunderbirds]

Hi all.

I've had the 1999 M1123 for just about a year now, and in the past two months the batteries have been drained (more likely the battery that is connected to the TCM). In about 10 days the voltage drops below 11.5 V. I have been able to let the truck sit for up to 5 weeks without any change before.

I have read so much about the TCM solenoid behind the commanders seat. Are there other know culprits?

I've measured about 30 mA draw, and I know just enough about DC electricity that that is too much. Would anyone be able to tell me the best troubleshooting methods, and sequence which components to check? No accessories added, pretty much stock setup.

I'm a decent mechanic, not so much electrician/avionics tech.

Thanks in advance.

 

[Mogman]

Well you can start by disconnecting things until you confirm the problem device.
If the TCM power relay was stuck you should have a trans light on all the time.
Start by disconnecting the batteries, then unplug the TCM harness at the TCM and then reconnect the batteries and test again.

 

[Thunderbirds]

Well you can start by disconnecting things until you confirm the problem device.
If the TCM power relay was stuck you should have a trans light on all the time.
Start by disconnecting the batteries, then unplug the TCM harness at the TCM and then reconnect the batteries and test again.

No Trans light. Good news. I will get to the TCM shortly, after I replace the fuse in my multimeter. Word for the wise, be careful which measurement range you chose before measuring... The fuse in the meter WILL blow

 

[Mogman]

No Trans light. Good news. I will get to the TCM shortly, after I replace the fuse in my multimeter. Word for the wise, be careful which measurement range you chose before measuring... The fuse in the meter WILL blow

I have one meter that flashes a warning light if you select a measurement type that is not compatible with the way the leads are plugged in, I thought that was pretty cool