dim dip, whats that all about?
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dim dip, whats that all about?
can someone tell me what the dim dip resistor thingy actually does in reality when you turn the lights on etc? can it be just disconected with the 2 wires left apart or do the wires need to be connected together? cheers,, Josh
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How it works...
Basicly when your on the sidelights and the engine is running (well, the key is in the run position) it puts the dipped beam on at reduiced intencity - probubly around 9v instead of 14v (well, you probubly don't have 14v through voltage drop in coroded terminals/switches, if you do clean them up so 14v is possable you'll be able to see where your going, this is what relays help achive) which makes it really dim - the dip switch doesn't affect it, its always the dipped beam being run. Turn the headlamps on properly and dimdip is switched off, though the resistor will still have a voltage in it when your useing dipped beam as its then fed from the bulb side - no current will flow through it though as its then disconected at the switch on the dash.
Why's it there...
The idea was to stop people driving around on sidelamps which is prittymuch illegal anyway (not that anyone seems to notice) but provide less light than proper headlamps for use in lit towns where people didn't feal the need to use full headlamps. It was something only the UK demanded from the mid 80's (so you only find it on the later UK spec vans) but the EU deamed it ilegal for the UK to demand seperate lighting standards to the rest of europe so in the 90's most manufacturs stopped fitting it, though my mates 2001 T4 seems to have it. Another mates 97 golf didn't have it! Its no longer required on any vehicle.
Whats it for...
If like me you thing you eather need your lights on (full headlamp obveously, as sidelamps are for parking at night and aren't bright enough to increase visability in daylight) or you don't, so you only need an ON/OFF switch. Dimdip is pritty pointless now. I have found it usefull when driving into a campsite at midnight though, reduices lighting up everyones tents too much, but thats it. Its the only obsolete part on your van you don't need to care about.
Why desable it...
If your wireing is staying standard then leave them be, they've done no harm for around 20 years so far. If your fitting relays to your headlamps (not a bad idea as said above) though dimdip can cause problems. If you fit the relays before the fusebox (so all the original headlamp fuses are still useable) dimdip will still work properly and your headlamps should still be brighter. If you fit the relays after the fusebox the 10 or so volts dimdip pumps out is enough to trigger the relays so dipped beam will come on at full power instead of reduiced power. Unplug the resistor and you'll just get sidelamps when in the middle position regardless of if the key is on. Proper headlamps will always work normally regardless of what you do. Just remember the plug will remain live when on dipped beam so it can short, though that shouldn't be an issue if the plug isn't damaged as they are designed to be insulated when unplugged.
Basicly when your on the sidelights and the engine is running (well, the key is in the run position) it puts the dipped beam on at reduiced intencity - probubly around 9v instead of 14v (well, you probubly don't have 14v through voltage drop in coroded terminals/switches, if you do clean them up so 14v is possable you'll be able to see where your going, this is what relays help achive) which makes it really dim - the dip switch doesn't affect it, its always the dipped beam being run. Turn the headlamps on properly and dimdip is switched off, though the resistor will still have a voltage in it when your useing dipped beam as its then fed from the bulb side - no current will flow through it though as its then disconected at the switch on the dash.
Why's it there...
The idea was to stop people driving around on sidelamps which is prittymuch illegal anyway (not that anyone seems to notice) but provide less light than proper headlamps for use in lit towns where people didn't feal the need to use full headlamps. It was something only the UK demanded from the mid 80's (so you only find it on the later UK spec vans) but the EU deamed it ilegal for the UK to demand seperate lighting standards to the rest of europe so in the 90's most manufacturs stopped fitting it, though my mates 2001 T4 seems to have it. Another mates 97 golf didn't have it! Its no longer required on any vehicle.
Whats it for...
If like me you thing you eather need your lights on (full headlamp obveously, as sidelamps are for parking at night and aren't bright enough to increase visability in daylight) or you don't, so you only need an ON/OFF switch. Dimdip is pritty pointless now. I have found it usefull when driving into a campsite at midnight though, reduices lighting up everyones tents too much, but thats it. Its the only obsolete part on your van you don't need to care about.
Why desable it...
If your wireing is staying standard then leave them be, they've done no harm for around 20 years so far. If your fitting relays to your headlamps (not a bad idea as said above) though dimdip can cause problems. If you fit the relays before the fusebox (so all the original headlamp fuses are still useable) dimdip will still work properly and your headlamps should still be brighter. If you fit the relays after the fusebox the 10 or so volts dimdip pumps out is enough to trigger the relays so dipped beam will come on at full power instead of reduiced power. Unplug the resistor and you'll just get sidelamps when in the middle position regardless of if the key is on. Proper headlamps will always work normally regardless of what you do. Just remember the plug will remain live when on dipped beam so it can short, though that shouldn't be an issue if the plug isn't damaged as they are designed to be insulated when unplugged.
Glen Syncronaut: 113 - 1992 JX Syncro pannel van