Reverse light always on.

Currently lining inside of defender with aluminium banked sound deadening insulation. So various bits taken apart.

Reverse lights and brake lights weren’t working. Read the circuit diagrams and realised both on same fuse.

replaced fuse and still no reversing light But realised my hand was getting mighty warm. Idiot that I am the reversing live feed was resting on aluminium sound proofing.

ouch.

anyway sort that out and let it cool. Plug it all back in and reversing lights on all the time.

checked the connections with test lamps and meters all seems fine. So I am assuming it’s likely to be the switch does that sound likely.
Tested the feed on other side and it’s also always on.

mid there anything else I should be looking for? Thanks

The switches are a weak point, most times they just need adjusting
Awkward place Iirc?

What gearbox is it? As far as I remember the LT77 has a reverse switch you can screw out and adjust with a lock nut, the R380 is one you just screw in all the way. I'd just replace it, they're not expensive at all

the_wolf said:

What gearbox is it? As far as I remember the LT77 has a reverse switch you can screw out and adjust with a lock nut, the R380 is one you just screw in all the way. I'd just replace it, they're not expensive at all

Click to expand...

R380. So I’ll give it a go.

The LT77 original switch is the same thread as the difflock switch in the Tbox. I’m not sure if the R380 is the same, but the difflock switch was about £12, the LT77 reverse light switch was around £90.

Have you tested the reverse light switch?

mick 1986 said:

The LT77 original switch is the same thread as the difflock switch in the Tbox. I’m not sure if the R380 is the same, but the difflock switch was about £12, the LT77 reverse light switch was around £90.

Have you tested the reverse light switch?

Click to expand...

That’s my next step to remove panel in cab and test feed to switch.

Landy_Ben said:

That’s my next step to remove panel in cab and test feed to switch.

Click to expand...

The feed to the switch is ignition live, so you can assume for now that’s ok. Have you tested resistance across the switch? Why has this fault suddenly appeared? Have you done any work on the gearbox/Tbox?

mick 1986 said:

The LT77 original switch is the same thread as the difflock switch in the Tbox. I’m not sure if the R380 is the same, but the difflock switch was about £12, the LT77 reverse light switch was around £90.

Have you tested the reverse light switch?

Click to expand...

I think it's the same switch as on a Sherpa ...

mick 1986 said:

The feed to the switch is ignition live, so you can assume for now that’s ok. Have you tested resistance across the switch? Why has this fault suddenly appeared? Have you done any work on the gearbox/Tbox?

Click to expand...

I haven’t yet - but will


Not on the gearbox but blew the fuse when the cable in the rear of the cab got trapped under rubber mat and connected to the metal of the soundproofing. So assuming that did something to the switch.

Landy_Ben said:

I haven’t yet - but will


Not on the gearbox but blew the fuse when the cable in the rear of the cab got trapped under rubber mat and connected to the metal of the soundproofing. So assuming that did something to the switch.

Click to expand...

I wouldn’t expect that to have done anything. If it wasn’t in reverse, then that part of the circuit should have been dead.

Landy_Ben said:

I haven’t yet - but will


Not on the gearbox but blew the fuse when the cable in the rear of the cab got trapped under rubber mat and connected to the metal of the soundproofing. So assuming that did something to the switch.

Click to expand...

Shouldn't have they're just a push-to-make switch ... might want winding out a bit so that it only makes when reverse is selected ...





Have a read here; someone with a similar problem ...
https://www.landroverexpedition.com/technical/r380-reverse-light-switch/

mick 1986 said:

I wouldn’t expect that to have done anything. If it wasn’t in reverse, then that part of the circuit should have been dead.

Click to expand...

I think I had missed it yesterday morning when I drove it which included reversing. Then when checking lights before putting rear cover panel back on realised I had no reverse or brake lights. So traced that to fuse. Put
In reverse to check if working and still off. So while double checking wires it all heated up til I realised hidden wire. By which point it was hairdryer hot.

turned off and reconnected everything and this is when I realised lights were perm on.

all my fault - not being careful enough.

Landy_Ben said:

I think I had missed it yesterday morning when I drove it which included reversing. Then when checking lights before putting rear cover panel back on realised I had no reverse or brake lights. So traced that to fuse. Put
In reverse to check if working and still off. So while double checking wires it all heated up til I realised hidden wire. By which point it was hairdryer hot.

turned off and reconnected everything and this is when I realised lights were perm on.

all my fault - not being careful enough.

Click to expand...

Might have a wire short then, insulation toasted through...

That'll need to be cut out and replaced, or the whole thing could get hot ...

Dippypud said:

Might have a wire short then, insulation toasted through...

That'll need to be cut out and replaced, or the whole thing could get hot ...

Click to expand...

thought that might be the case - this is rear left as uk Defender. But the wiring is also there on rear right (same for fog light so there was only one loom regardless of drivers side) and the feed on the right is also perm on.
Excuse my ignorance but single wire with insulation compromised is that shorting as it runs on something else? Trying to work out how the feed is now perm on with ignition other that switch being stuck in reverse.

Landy_Ben said:

Currently lining inside of defender with aluminium banked sound deadening insulation. So various bits taken apart.

Reverse lights and brake lights weren’t working. Read the circuit diagrams and realised both on same fuse.

replaced fuse and still no reversing light But realised my hand was getting mighty warm. Idiot that I am the reversing live feed was resting on aluminium sound proofing.

ouch.

anyway sort that out and let it cool. Plug it all back in and reversing lights on all the time.

checked the connections with test lamps and meters all seems fine. So I am assuming it’s likely to be the switch does that sound likely.
Tested the feed on other side and it’s also always on.

mid there anything else I should be looking for? Thanks

Click to expand...

yes feed upstream of the switch is ‘always’ on and the switch completes the connection, I suspect your switch has failed or needs winding out a bit

Landy_Ben said:

thought that might be the case - this is rear left as uk Defender. But the wiring is also there on rear right (same for fog light so there was only one loom regardless of drivers side) and the feed on the right is also perm on.
Excuse my ignorance but single wire with insulation compromised is that shorting as it runs on something else? Trying to work out how the feed is now perm on with ignition other that switch being stuck in reverse.

Click to expand...

You need to do a resistance test across the switch now. If that comes back as 0 ohm and not opening, then it’s permanent closed. So not working. I would remove it from the gearbox to test it, as it’s easy to depress the button and make the switch open and close.

flat said:

yes feed upstream of the switch is ‘always’ on and the switch completes the connection, I suspect your switch has failed or needs winding out a bit

Click to expand...

does the R380 switch wind? I thought it was just the previous model.

Landy_Ben said:

does the R380 switch wind? I thought it was just the previous model.

Click to expand...

Sorry not sure I only have experience of the lt77 - missed that that is an r380

I would take the reverse switch out and test it, I could have got overloaded when heating up the aluminium and melted the contacts together inside or something.

Just take the bloody switch out and test it! The contact pin that depresses may just be stuck.
Once you’ve tried the switch, then start worrying about faulty wiring.

Landy_Ben said:

does the R380 switch wind? I thought it was just the previous model.

Click to expand...

It doesn't, the R380 switch is wound in all the way for it to work.
He's probably just got a stuck switch, something simple to fix