Help with Off-MOM carling switches.

Hi all - I'm fairly new on here and I've only had a defender for a few months so please bear with me!

I've just spent two days fitting a dual battery system and Raptor dash to my TD5, and I've hit a stumbling block with two switches - one for the heated screen, and one for the rear fog light.

I've purchased the same replacement carling switch for both - a off-mom FOG type that mudstuff recommended, needing a power in, power out, feed from relay, two earths and a feed from sidelights.

However the wiring's thrown me completely. The LR heated screen switch has only four wires - earth, feed from sidelights, then two wires, one leading to the timer relay, and one to the heated screen and it's relay. The fog light switch is worse, not matching the LR wiring diagram!

If anyone can help I'd be your friend forever!!

have yu asked mudstuff?

That's my next port of call on Monday - I was just hoping someone on here could point me in the right direction!

Nothing doing - I've already got all the mudstuff online info to hand, but the carling switch pins have additional inputs over and above the LR switches that have me befuddled.

pepperedwelly said:

Hi all - I'm fairly new on here and I've only had a defender for a few months so please bear with me!

I've just spent two days fitting a dual battery system and Raptor dash to my TD5, and I've hit a stumbling block with two switches - one for the heated screen, and one for the rear fog light.

I've purchased the same replacement carling switch for both - a off-mom FOG type that mudstuff recommended, needing a power in, power out, feed from relay, two earths and a feed from sidelights.

However the wiring's thrown me completely. The LR heated screen switch has only four wires - earth, feed from sidelights, then two wires, one leading to the timer relay, and one to the heated screen and it's relay. The fog light switch is worse, not matching the LR wiring diagram!

If anyone can help I'd be your friend forever!!

Click to expand...

The TD5 Defender's Heated Front Screen switch and Rear Fog Lights switch both work in the same way.

The Heated Front Screen switch makes a momentary path to earth for the HFS Timer Relay.

The Rear Fog Lamps switch makes a momentary path to earth for the "ECU - Rear Guard Fog Lamp".

Both switches have a live that comes from the output side of their Relay/ECU to Pin 5, to light the 'tell-tale' warning light when the HFS or Rear Fog Lights are on.


The wiring colours for each of the switches, are -

Rear Fog Lights

Black/Grey trace (Pin 1) - 'Trigger' circuit from Rear Fog Lamps ECU

Red/Orange trace (Pin 2) - Live from dash illumination

Black (Pin 4) - Earth

Red/Yellow trace (Pin 5) - Live from Rear Fog Lamps ECU (for switch 'tell-tale')


Heated Front Screen

Pink/Orange trace (Pin 1) - 'Trigger' from HFS Timer Relay

Red/Orange trace (Pin 2) - Live from dash illumination

Black (Pin 4) - Earth

Purple/Grey trace (Pin 5) - Live from HFS Timer Relay (for switch 'tell-tale')


(Pin 3 isn't used on either switch)


How any of the above translates to a Carling switch, I'm afraid that I don't know

.

Thanks mate - that breaks the wiring diagram down for me! I think I'll get my multimeter out and play with the carling switch to see what sends what where.

pepperedwelly said:

Thanks mate - that breaks the wiring diagram down for me! I think I'll get my multimeter out and play with the carling switch to see what sends what where.

Click to expand...

What's the part number of the Mudstuff Carling switches that you've bought?

I'll have a look at their wiring instructions and see if I can work-out what goes where.

.

It's a off-MOM FOG switch,

I'm thinking link the power out and feed from relay to the timer relay, and the power in to the trigger, obviously earth and sidelight as normal. Sound about right? This would go the same for the fog light (hopefully)

pepperedwelly said:

It's a off-MOM FOG switch,

Click to expand...

I've already had a look at their website, and that looks like the correct switch for both functions.

This is from their wiring guide -





I think that you should wire your switches, as follows -


Rear Fog Lights Switch

Black/Grey trace - Carling Pin 2

Red/Orange trace - Carling Pin 8

Black - Carling Pins 3, 7 & 9

Red/Yellow trace - Carling Pin 10



Heated Front Screen Switch

Pink/Orange trace - Carling Pin 2

Red/Orange trace - Carling Pin 8

Black - Carling Pins 3, 7 & 9

Purple/Grey trace - Carling Pin 10


That should work OK.

.

I'll get out and play first thing tomoz and let you know. Thankyou!!

All seems to be well - the foglight certainly works! However, the heated screen switch when depressed lights up for a second, then I hear the relay click back off and the light goes back out. Any ideas?

pepperedwelly said:

All seems to be well - the foglight certainly works! However, the heated screen switch when depressed lights up for a second, then I hear the relay click back off and the light goes back out. Any ideas?

Click to expand...

No idea

If it's wired-up as detailed above, then it should work.

You could try swapping the switches, to see if the fault is with the switch.

.

I had the same problem with the switch, the light would come on for a short time then go out. I had a few electricians look at it and they were stumped too because if it is wired up properly it should work. I even looked at other landrovers that had the and they were wired the same. I actually went through a few relays and they are not cheap, in the end I just wired it up as normal and I just switch it off after the screen clears and had no problems

I've now replaced the relay and all is well! Thanks for the assistance folks - much appreciated!

I have just wired my rear wiper/wash carling switch and all works well apart from having no orange illumination on switch when switch is on. The green illumination works fine with the side lights yet not the bar. Any ideas???

Same problems for me sort of. I'm migrating hazard and fog lights from near my right knee to a MUD mini pod on top of my dash. I've sorted out the hazard with no probs (and some help from MUD who are very good) but the fog has got us flummoxed.

My old MOM style fog switch (it's a Y-reg TD5) had just 2 wires coming out of it: black (with white trace) from pin 2 and black (no trace) from pin 3. That was it!

The new carling MOM switch however requires the following:

• Pin 2 - power in
• Pin 3 - power out
• Pins 7 & 9 - earth
• Pin 8 - sidelight feed in
• Pin 10 - feed from relay

I'm clueless here, I'm definitely at the 'ham fisted amateur' end of the enthusiast scale rather than the proficient auto electrician end!

• What are those original 2 wires? Are they power in and out? Which pins do they go into on the Carling?
• For pins 7 & 9, do I just splice into the earth supply from my hazard switch to supply earth to the fog switch?
• How do I locate and wire into the dash fog warning light supply wire for pin 10?
• Likewise, how do I locate and tap into the sidelight feed?

Any help would be VERY much appreciated.

Cheers

Nigel

Carling switches seem to be slightly odd in operation sometimes.

I recently fitted an ON-OFF-ON switch for my engine-fan (OFF = automatic operation, ON1 = manual run, ON2 = manual over-ride off) and despite my expectation being that the green bar would light in both of the ON positions (as stated on the website) it only lights in one of the positions.
I queried this with MUD (the supplier) and they said that they had just had a similar query from someone else and when the checked with Carling they said this was correct. Didn't sound right to me but in all fairness they sent me (FOC) a Carling red / green warning light c/w a pair of FAN symbols which actually does a better job of telling me what is happening rather than just seeing the green bar.