04 overdrive switch light headache

kilohotel

New Member
Original poster
Supporting Member
Joined
Oct 31, 2022
Messages
11
Location
San Francisco
My OD switch indicator light wasn't working (but the switch/feature itself was - i would use it on highways regularly), so I installed a new OEM switch.

The new OEM switch has the same issue: the switch works, but indicator light doesn't.

I also checked the bulbs themselves using this thread: https://wranglertjforum.com/threads/overdrive-switch-light.39757/ and the filaments seem fine.

I'm at wits end with this, anyone have any ideas what the issue might be? Thanks!
 
I'm at wits end with this, anyone have any ideas what the issue might be? Thanks!


Based on the schematic, both bulbs and the OD operation all use the same ground.
The PCM then sends power back to the switch to light the bulb.
So it could be the PCM, or the wiring in between.
 
Based on the schematic, both bulbs and the OD operation all use the same ground.
The PCM then sends power back to the switch to light the bulb.
So it could be the PCM, or the wiring in between.

Thanks - by "both bulbs" you mean the text backlight and the indicator? The text backlight bulb works fine when I turn on the headlights, its just the OD indicator light that doesn't.
 
Yes.
The fact that the OD off function (and the backlight bulb) work should mean that the indicator bulb should work; unless it's not getting the voltage it needs from the PCM.
Have you inspected the connector that the switch plugs into?