6 replies to this topic

[danoz24]

hey chaps, newbee here. Ok... i have been working on my 1990 classic mini electrics by installing a modern set of indicator/wiper stalks and have a slight problem/difficulty understanding the purpose of the dim/dip relay. i have used a fair amount of relays with my new install as the new stalks cant handle the original amp load - i also understand that relays 'take the load' and can require a small current to activate but having 7 different pins in the dim/dip relay is sending me crazy. What i have achieved is side lights (red/green wire) working, main beam 'FLASH' (blue/white wire) working, but not the main beam constant (blue wire) or the dipped beam (red/blue wire) working. I can rig the circuit without the blue wire at all and have the blue/white 'FLASH' wire as my constant main beam as well as for the 'FLASH' - but will this method cause problems? - is the original method with the blue wire designed to steer clear of my possible solution? The other problem with my dipped beam - could i simply just bypass the relay at all - will this work and will the dipped beam be a efficient and still as safe as possible - i dont want to cause any risky hazards. Finally, going by the haynes manual, the dim dip relay does have some communication with the dipped beam which comes from the lighting switch through a red wire (why is this if it also connects straight to the sidelights also?). i seem to have a brown/orange wire that goes to the dim/dip relay also which is a very close feed to the starter motor (why would this be?). there is an earth connection to the relay, the red/blue wire to the dipped headlights, green wire to the dials, and a blue wire from the light switch.

thanks so much for reading, please help!!!!


thanks again

dan

[taffy1967]

The dim dip lighting system only affects the main headlamp bulbs and when you switch on the ignition whilst only having you're side lights on, the main headlamp bulbs glow dimly.

The 15amp in-line fuse with the Brown/Orange Wire controls the Dim-Dip Lighting and apart from the orange relay box mounted under the dash. You should also be able to see the main dim-dip unit mounted behind the radiator.

Edited by taffy1967, 13 June 2007 - 02:55 PM.

[Dan]

Well all the wires sound like they are connected up right. It works just the way Taffy says, can't think what would be the problem unless the fuse is blown. What exactly do you want to know?

You understand that using multiple relays can cause you feedback problems in the relay coils which will prevent any of them ever turning off I hope? How many have you used exactly? You don't need that many, there aren't many high current devices in the stalks really. Only the actual headlamps and relaying these is simple and has been covered on here at length.

[danoz24]

ok kinda sorted the situation. no cheating as of yet, just followed the wiring diagrams and connected what it says in the haynes manual. what i wanted to know or understand in the first place was the breakdown of exactly how the dim/dip relay works referencing such things as where the power comes from when something is switched on and what becomes live when the relay is activated. and basically what wires go where and do what. however had a fiddle last night and got the dipped beam working last night but only when ignition is off. when i turn the key to position 2 the dipped beam shuts off but the side lights are still on. i checked the voltage on the orange and brown wire in the dim/dip relay and it goes from 12.4 volts (ignition off) to 5.0 volts (ignition on) - and the same goes for the dipped beam red and blue wire. what could this be? how might i get the 12.4 volts back to the dipped beam through the relay?

cheers again

dan

[Dan]

The system works to prevent you driving the car on sidelights only. So that while the ignition and sidelights are on together without the dipped beam being switched on, the dipped filaments are connected to the output of a large ballast resistor mounted behind the radiator. That gives the roughly 5 volts you measured to power the lamps to a lower intensity than normal. The output of the ballast should always be present at the relay while the ignition is on but won't always be 5 volts depending on what's connected to it. The relay should be connecting the lamps to the thick blue/brown wire connecting the relay to the stalk switch every time it detects voltage at the thinner blue signal wire from the light switch. It sounds like the relay isn't getting the 12v signal from the light switch that tells it when the headlamps are on. It's a thinner plain blue wire in the relay base and should be reading 12v whenever the master lighting switch is in the headlamp position. I think this comes from the stalk switch connector so if you've been altering those you may have broken it.

[danoz24]

ok cvool that sums up a lot, ill have a think about my circuit and use your helpful info to patch things up.

great stuff

thanks again

dan

[danoz24]

actually come to think about it i am pretty sure that when i locked the main beam it was a thick blue/red wire (located more towards the edge of the central assembly) that connected to the thick blue wire (located more towards the centre). but just like you stated, the blue/brown wire should connect here from the relay - am i right?