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headlight/side light fault

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Guys, ive just come to fix my wobbly headlight switch on the 300tdi 90, the nut had come loose. Once all back together i went to test my lights and now seem to have a fault. I cant seem to get just sidelights alone unless the key is turned to the off position this is on stage 1 (the 1st click from the off postion) of the headlight switch. A soon as the key is turned to stage 1, the headlights come on, but are only faint. So i then push the headlight switch to the second setting which i believe should be dipped beam and the headlights brighten. This is all while the engine is off! The same happens once the engine is started, sidelights are on but so are the headlights but only faint, then i push the headlight switch to setting two and the headlights brighten.

Any ideas? This didnt seem to happen before i messed :unsure:

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your vehicle has a dim dip system fitted.

light switch at position 1 with ign/engine off should give front sidelights/rear taillights for parking

light switch at position 1 with ign on & engine running should illuminate the front sidelights & rear tail lights & headlights at reduced powr [dim dip] the dim dip system should not work with the ign on & engine off, it gets a signal feed from the engines oil pressure switch when engine is running & creating oil pressure.

when the 2nd position is selected dim dip is disabled & normal dip beam is activated & sidelights/tail lights, main beam is selected by pushing the lefthand column stalk forward.

sounds like the dim dip [pink relay behind instrument pack] is faulty.

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western, mine is doing exactly what your saying. But i cant just get side lights when the engine is running so in that case is everything correct and i will never have just side lights?

you can't & that's the way the system operates, it was meant to prevent vehicles being driven at night on sidelights only, reason was to improve road safety for pedestrians in built up areas with street lighting

only way to get sidelights only with engine running is to remove the dim dip relay & fit a jumper wire across 2 of the terminals, but I don't know which 2 terminals, the answer to that is on this forum somewhere.

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happy to help,

not sure what happens if the relay fails, but on the previous dim dip system if the transformer failed it would leave the nomal dip headlights on regardless of switch/enging on/off positions -- the easy fix is unplug & normal service minus dim dip resumes,

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