Wiring

[jmustian]

Does anyone know which fsm I should use on my 69 300 that was made Nov 68?
I have the 69 manual but I've pulled apart most of the wiring harness and the wires don't seem to match.
I started to trace and repair no backup lights. The 69 fsm shows the black and black w stripe from the trans to the fuse box. Good switch good ground, no lights. I pulled apart fuse box and it shows wires changed to white w/ white stripe inside fuse box. Fsm shows white going to purple wire at floor sill and purple wires go to back up lights. No circuit. Fsm shows purple wires change to white then go through fuse box. Simple circuit. Trying to trace two white wires, they go up into dash and I pulled dash and still haven't got to end of white wire. Fsm does not show all this.
Back up lights have good ground and work fine if I jump power to purple wire connector at drives kick panel.

 

[MrMoparCHP]

The 69 manual is the correct one, I have found minor errors but generally they are correct.

Show a copy of the page and highlight the area you are looking at.


Alan

 

[jmustian]

The 69 manual is the correct one, I have found minor errors but generally they are correct.

Show a copy of the page and highlight the area you are looking at.


Alan

Just trying to get b/u working. I'll send it soon as I can. Just about got whole harness out haha. 3 days for a dang light.

 

[jmustian]

Just trying to get b/u working. I'll send it soon as I can. Just about got whole harness out haha. 3 days for a dang light.

The trans has the 3 wire switch and neutral switch works fine. One side of b/I switch and other side hot. Can't get lights to work or find which leg is not working. According to fsm switch closes and completes circuit but even operating another switch by hand and grounded. Lights won't come on. Don't think it would be switch or trans since neutral switch works

 

[jmustian]

Mess haha

 

[jmustian]

Ignore the heavy red marks. They were in book when I got it.
Diagram shows white wires coming into and leaving fuse box.
Diagram shows connector and turns to violet on other connector.
Hots and grounds and fuses test good in fuse box. Lights work when applying power to violet wire.

 

[1970FuryConv]

Does anyone know which fsm I should use on my 69 300 that was made Nov 68?
I have the 69 manual but I've pulled apart most of the wiring harness and the wires don't seem to match.
I started to trace and repair no backup lights. The 69 fsm shows the black and black w stripe from the trans to the fuse box. Good switch good ground, no lights. I pulled apart fuse box and it shows wires changed to white w/ white stripe inside fuse box. Fsm shows white going to purple wire at floor sill and purple wires go to back up lights. No circuit. Fsm shows purple wires change to white then go through fuse box. Simple circuit. Trying to trace two white wires, they go up into dash and I pulled dash and still haven't got to end of white wire. Fsm does not show all this.

Perhaps someone did some rewiring.

Before pulling everything apart: I would Check continuity from connector at the auto trans 3-prong switch to the fusebox to determine whether you have continuity to power. Then check continuity from the backup light sockets to the other outside terminal of connector at the auto trans 3-prong switch. I would want to know which side of the switch circuit is the problem.

You can also check good continuity across the switch with shifter in reverse,

 

[jmustian]

Perhaps someone did some rewiring.

Before pulling everything apart: I would Check continuity from connector at the auto trans 3-prong switch to the fusebox to determine whether you have continuity to power. Then check continuity from the backup light sockets to the other outside terminal of connector at the auto trans 3-prong switch. I would want to know which side of the switch circuit is the problem.

You can also check good continuity across the switch with shifter in reverse,

I totally made a new harness yesterday from transmission to fuse box as it had been patched several times. I have great continuity from trans to fuse box, across fuses, and from connector in left kick panel to lights. Replaced trans switch and still likes don't work. Checked trans and neutral switch works. The fsm shows a simple loop but trying to trace the white wires is not a simple loop and they go up somewhere in the harness towards the glove box which seems 100% wrong.

 

[jmustian]

Just remembered I had trans rebuilt last year so maybe I'm getting neutral safety but not reverse. I'm told there may be different parts in different age trans. It was not my original because the sun gears had blown up.

 

[1970FuryConv]

I totally made a new harness yesterday from transmission to fuse box as it had been patched several times. I have great continuity from trans to fuse box, across fuses, and from connector in left kick panel to lights. Replaced trans switch and still likes don't work. Checked trans and neutral switch works. The fsm shows a simple loop but trying to trace the white wires is not a simple loop and they go up somewhere in the harness towards the glove box which seems 100% wrong.

Just remembered I had trans rebuilt last year so maybe I'm getting neutral safety but not reverse. I'm told there may be different parts in different age trans. It was not my original because the sun gears had blown up.

If you have the stock 3-prong switch at trans, you should have continuity across the outside prongs when the car is shifted in reverse. In other gears, you should not have continuity across those outside prongs. Center prong is Neutral Safety.
*Did the reverse lights ever work after the trans was rebuilt?
If not, maybe it's an internal adjustment issue. Since you have replaced the switch and still have no lights, I doubt the switch is the problem.

As to the connector at the 3-prong switch, sounds like you have good continuity to power from fusebox at one outside terminal.
Generally, you need continuity from the other outside terminal through the firewall bulkhead connector to the left kick panel connector. I suspect this part of your wiring harness is the problem.

 

[jmustian]

Thanks. Couple spots to check. I got dash out and a couple wires there to repair also. Got to get ready for spring hahaha