TC29D issue with parking brake light

[dqdave1]

Replaced bulb as it was bad. Now light stays on always. Tried to adjust the switch, no difference. Removed switch, tested, tested good , but light is on even with switch removed.
Placed jumper in exposed plug to switch, no difference.
Anyone have a suggestion??

 

[RayIN]

Socket is being back-fed by something.

 

[dqdave1]

I was hoping someone had the same issue and figured it out.
I understand bulb is getting power but since it is a circuit board, may be chasing something impossible.

 

[nyone]

Sounds like the circuit board..and a good time to just remove the bulb.

 

[ruffdog]

Most times, a light like that turns on when the switch completes the circuit to ground. If the wire going to the switch is pinched or shorted to ground, the light would stay on all the time. Test the wire...is it grounded? I would trace the switch wire back to find where it is grounded. If not grounded, then there is something wrong in the controller.

 

[dqdave1]

Agree, has to be grounded to make connection. Not grounded at pigtail where switch plugs in .
Will have to pull instrument panel and see what I find there
Thanks for info.

 

[ruffdog]

Agree, has to be grounded to make connection. Not grounded at pigtail where switch plugs in .
Will have to pull instrument panel and see what I find there
Thanks for info.

Going by this diagram...
https://www.tractorbynet.com/forums...ew-holland-tc33d-2-style-of-harnesses.468559/
...the wire goes from the switch to the inst panel. Check for continuity to ground from the switch wire at connector. You could use an ohm meter and have the key off. If it is grounded, unplug the connector at the inst panel and check the same wire. If it is grounded, you have a short. If not, the problem is in the panel.