TC Lockup light (again)

[FMcClaren]

Help
I put a TC lockup light on the OR/BK wire in center PCM plug with LED and keyed 12 volts.
The light came on when i turned key but went out when truck started and everything worked
good. This morning the light came on and stayed on and Trans wouldn,t shift until i
unhooked the light. Any ideas?
THANKS
Mac B

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01 2500 Bright silver QC A/T 4x4 LB 3. 54 50 gal. tank tool box combo. Autometer gauges. Full length DC boards. DC flip out towing mirrors. chrome exhaust tip, front bumper S/S inserts. Reese 5th wheel hitch. 25 ft. Joyco eagle 5th wheel.

 

[Hale on wheels]

I don't have a service manual yet, but I believe the PCM grounds the OR/BK wire for a lock up signal, right? It could be that +12V is a higher voltage than the wire carries while not in lock up. You can use a multi-meter to see what the voltage on the wire is while not in lock up (without the LED in). But, since I don't have a schematic, I don't think I'll be too much help. I guess I really need to order a manual.

 

[FMcClaren]

With the key on theres nothing in the wire
with the engine runing there is 12 volts in the wire. I got the LED at Radio shack and it,s 12 VDC-15mA. I got a 98 manual and a 01
and there is a differancein the way it,s
wired. but I,m not to good at reading these things.
Thanks
Mac B

------------------
01 2500 Bright silver QC A/T 4x4 LB 3. 54 50 gal. tank tool box combo. Autometer gauges. Full length DC boards. DC flip out towing mirrors. chrome exhaust tip, front bumper S/S inserts. Reese 5th wheel hitch. 25 ft. Joyco eagle 5th wheel.