School me on interior dome/courtesy light circuits... (1 door = no illuminatin') (1 Viewer)

[Taylorious]

Howdy,

Title's self explanatory... And I ***think*** I've isolated the cause of this issue, but need confirmation from someone wiser with chassis electrical than I am.
Here's the related electrical diagram for the chassis section I'm working with:

ISSUE:
Dome / "Courtesy" light illuminates for 3 of the 4 doors.
FR Driver, FR Passenger, and R Driver all illuminates the dome lamp... but the R Passenger does not illuminate.

I replaced the switch with an OEM part, and still have no dome/courtesy trigger when I open the door.
Sanded the chassis contacts.

Questions I need answered:
1) Does the RED-BLUE wire in the chassis dome light circuit function like the Horn circuit, in that a grounding triggers the horn?
2) If so, would I see a 12v current at the RED-BLUE chassis wire at all times?

See edited diagram below for visual explanation:

THANKS 'Mud.

 

[Dr. John]

1) YES
2) YES

The hot R/Bl to the RR must be somehow disconnected.

 

[Taylorious]

1) YES
2) YES

The hot R/Bl to the RR must be somehow disconnected.

Thanks man. Sure it's something I'll chase down in the chassis.

 

[CruiserWil]

Thanks man. Sure it's something I'll chase down in the chassis.

If you fixed this issue, what was the cause?

Just a side comment--that diode in the circuit is intriguing...maybe this is an FJ62 wiring diagram. It's not in my FJ60 diagram.

 

[Taylorious]

If you fixed this issue, what was the cause?

Just a side comment--that diode in the circuit is intriguing...maybe this is an FJ62 wiring diagram. It's not in my FJ60 diagram.

Sheesh... I haven't fixed this. Put my RTT ladder on that side and gave fewer cares.

I did open the Pass side fender well and paneling and chase the harness... testing as I went... and (this was 6-7mo ago) I believe that there was no power on the pass rear door Red/Blue wire...

Further; I replaced the switch, so that's there for when I want to run this whole thing down... but; It seemed inconsequential and a rather non-issue right now.

 

[rhah]

Sheesh... I haven't fixed this. Put my RTT ladder on that side and gave fewer cares.

I did open the Pass side fender well and paneling and chase the harness... testing as I went... and (this was 6-7mo ago) I believe that there was no power on the pass rear door Red/Blue wire...

Further; I replaced the switch, so that's there for when I want to run this whole thing down... but; It seemed inconsequential and a rather non-issue right now.

Got me beat, mine only works with the driver door

 

[CruiserWil]

Yeh, I've got a similar thing going on with my cargo hatch light. Per my wiring diagram, it's only activated by the cargo hatch switch, none of the other door switches. With yours, any individual door will activate both interior lights, which I like better. Is yours a 62?

 

[HemiAlex]

I'm leaving this as a note for myself.

I need to figure out why both of my rear doors don't actuate the dome light.

 

[Taylorious]

I'm leaving this as a note for myself.

I need to figure out why both of my rear doors don't actuate the dome light.

We’ll get it, ‘G. I’ll keep ya’ll posted.

 

[franklin40]

i have some of these gremlins too. my rear passenger door won’t light up and my hatch light is intermittent. i know i may sound like a dunce here but where exactly is the rear hatch switch? i’ve been looking for it and just don’t see it

mine is an fj62

edit: found this thread. good info here

How-to: Tailgate light switch restore

My tailgate interior light was flaky, so I finally pulled the latch/switch mechanism and did a proper repair. Works perfectly now. Anyone interested in a write up? Or, has this been covered elsewhere?

forum.ih8mud.com

 

[CruiserWil]

i have some of these gremlins too. my rear passenger door won’t light up and my hatch light is intermittent. i know i may sound like a dunce here but where exactly is the rear hatch switch? i’ve been looking for it and just don’t see it

Yeh, me too on an FJ60. I'm thinking the hatch switch is internal somewhere....

 

[bronco loco]

Something else to fix now. None of my doors activate the dome light but do activate the lights on the door panels.

 

[RredFJ40]

Wire harness for the right rear door leaves the interior near the left rear lights, crosses under the tailgate to the right lights and then the right rear door. Under the tailgate is the common area for the harness to get damaged.

 

[CruiserWil]

Wire harness for the right rear door leaves the interior near the left rear lights, crosses under the tailgate to the right lights and then the right rear door. Under the tailgate is the common area for the harness to get damaged.

Think you meant left rear door?

 

[CruiserWil]

Here's the 60 dome lights wiring diagram.

 

[fruitjack]

the hatch switch should be connected to the lock mechanism on the upper lift gate. open either the center or right access panel and you ought to see it. i had to replace mine because that switch was busted.

 

[RredFJ40]

Think you meant left rear door?

Which time? Pretty sure I got it right, at least for US spec.

 

[CruiserWil]

Which time? Pretty sure I got it right, at least for US spec.

Your post #13. Doggone, I mis-read it, you said it correctly. Good tip about where to look for right rear door harness damage.

 

[CruiserWil]

the hatch switch should be connected to the lock mechanism on the upper lift gate. open either the center or right access panel and you ought to see it. i had to replace mine because that switch was busted.

This tip helped, thanks. The center-right hatch access panel (on a 60) will reveal the situation. To test if the cargo hatch-latch light switch is bad, I by-passed it. I took the cargo dome light connector off the hatch-latch switch and grounded it to one of the hatch latch mounting bolts. Viola--I have a cargo light when the cargo light switch is set in the 'Door" position, for the first time in a decade or two I bet. So gotta clean up the hatch-latch switch per the above referenced thread. Small victories are nice too.