Where is my Dim Dip relay ?

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.

iguana

Member
Posts
41
Hi all
I am having problems with my headlamps.
Side lights work ok, flash on main beam works ok but the normal beam does not work.
I have checked fuses , switches and bulbs all ok.
Some posts mention dim dip relay (pink)behind the instrument panel but I only have two yellow ones ?
image.jpg

It's a 1991 110 CSW, see pics of relays below, which one is the dim dip ?
Thanks
image.jpg
 
you cant unscrew except from the front ,you can fit another and tie wrap next to it , or work your way through the wiring ie trying each light
 
Not all Defenders have a dim-dip, could be the main lighting stalk at fault ...

If you have the thing that is in James pic, (it'll be behind the instrument pack as he says), try unplugging it ... then try the lights again ...
if all is well [except dim dip headlights] you've solved the problem ...
but then it could be your oil pressure switch ... that sends a signal to the dim-dip ...
 
Last edited:
My dim-dip relay failed a while ago. The type shown above can just be disconnected and the lights should work as normal headlights. All it does is pass a lower voltage to the dipped headlight connection when the side lights are on and the oil pressure switch is open. The oil pressure switch is used as an indication that the engine is running, so you can have just the side lights on when parked.

The other type wires directly into the dipped headlight connection, so if it's failed then the dipped headlights won't work at all.
 
Ok, I can see why they did it, on the 300 oil pressure switch is only connected to the oil light.

Then you'll have the pink relay ? if I remember right ...
but they can come in yellow ... this is Rover Group leftovers ...
but some up-market ! models have the relay, some have a 'dummy' relay ... stop laughing at the back ...
This dummy relay provides a 'short circuit' connection between contacts C048-8 and C048-2 on the lighting circuit ...
RELAY-DIMDIP.jpg
this can be the problem, even if it is a rubbish job in an expensive case, it can melt the base and die the same as any other ...
 
My dip beam packed up the other day, after spending hours changing relays checking earths fuses, headlight switch etc etc turned out to be the main flash/ indicator stalk. Put a new one in and headlights came back to normal.
 
I have now changed the dim dip relay as shown in the picture from James, still no good, I then changed the stalk switch that puts the side lights/ main lights on, costs are mounting and I still can't get the f##ker to work !The fuses are ok.Any suggestions what to try next ?
Thanks
 
This is how it is supposed to work:-
side lights on engine off and ignition off - just side lights on
side lights on with ignition on - dip beam comes on dim as well, reason being is that your not supposed to travel on the highway with just your side lights on, which you cant if the engines running and the ignitions on!

Check all connectors on all lights, (front and back), check all earths ...
If you have changed a bulb recently make sure that it is the correct type / size ...
If all your earths are all good and you can get 0 Ω resistance across all circuits, then you can go hunting for the tricky stuff like broken wires...
 
after much hunting on mine, it was located behind the speaker on the drivers side, mine failed closed circuit, meaning my headlights were on "dim" permanantly.
 
I have now found the rear fog inhibitor relay, the wiring diagram shows the dip beam wiring goes through this relay.
Don't know how to check the relay except to get a new one but found a strange resistor type wire across the 85-86 connections (see pic) there is no continuity across 85-86 but there is 12v to 85 (orange wire) does anyone know what this is ? And are there any checks on this connector I can do ?
image.jpg
image.jpg
image.jpg
 

Attachments

  • image.jpg
    image.jpg
    156.1 KB · Views: 357
With regard to the headlamps, if you are on normal beam and flash onto high beam, the normal (dipped) beam will stay on. If you push the stalk forward into high beam mode, the dipped beam should turn off...
With the side lights then main lights on the fog light should illuminate - when you flash your headlights, what happens to the fog light ?
When you push the stalk forward to keep your high beam on, does your rear fog go out ?
 
I have now found the rear fog inhibitor relay, the wiring diagram shows the dip beam wiring goes through this relay.
Don't know how to check the relay except to get a new one but found a strange resistor type wire across the 85-86 connections (see pic) there is no continuity across 85-86 but there is 12v to 85 (orange wire) does anyone know what this is ? And are there any checks on this connector I can do ?
View attachment 93079 View attachment 93081 View attachment 93082

Looks like a diode ...
 
Back
Top