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MG MGF Technical - TF Headlamp Aim?

I think the aim of the headlights are too low, the MGR dealer says they're set right....

For cars about 20' away the dip lights won't pick up rear reflectors or number plates and range is about 25' after that darkness. As I said a bit low/short. Am I right?

Three options I 'spose

one, battle it out with dealer - yawn...

two, take it to the local MoT'r

three, fiddle myself...

If I go routes two/three are the beam adjusters the black plastic hexagonal nuts? Is the top one vert adj and the bottom one horiz?

Are the settings 1% Vertical (as embossed on light unit, 'F' is 1.4%) and 0% Horizontal (not indicated but that was the 'F' spec)?

Finally, how do I make sure they are set to RHD before I fiddle? The HB is far from clear. Diagram says LH headlight and yet shows a RH one and secondly the words say 'move lever to opposite of where it is now'. Am I correct in assuming the way to tell is the beam shape being an '/_' (for UK) or a '_/ (for Europe)?

Ian Walker

I'll try the last bit again!

beam shape being an '/_' (for UK) or a '_/ (for Europe)?


beam shape being an 'L' (for UK) or a '_/ (for Europe)?

Ian Walker

The aim of the headlights was too low, the MGR dealer was wrong or didn't check....

I chose two, take it to the local MoT'r and three, fiddle myself... (Volvo Main Dealer opposite the MGR Dealership!!! Spotless workshop, new equipment, very friendly techies, we set the beams together, him explaining what he was doing and why. We talked cars and they enjoyed doing an opposition’s car and didn't want paying. How refreshing!)

The beam adjusters are the black plastic hexagonal nuts. The top one is vert adj and the bottom one horiz.

The settings are 1% Vertical (as embossed on light unit, 'F' is 1.4%) [this corresponds to horizontal lines on the beam measuring equipment] and 0% Horizontal (not indicated but that was the 'F' spec) marked on the device as a circle.

We set it between -1.25 and -0.5% lines on the gear so just less than spec to get slightly better range.

"Finally, how do I make sure they are set to RHD before I fiddle?"

Easy really the beam pattern 'L' is obvious on the beam-measuring device.
Ian Walker

Hi Ian,

I thought it was just me that was under impressed with the night time vision on the TF.

However when I had it in the garage (for a new starter and bonnet adjustments), the Driver side had to be re-set. Now I can see that one side is higher (and more usable) than the passenger side. This however after being assured that both were set exactly level (Which to me sounds like 0%). Something tells me the dealer was providing false info (again).

Think I will take youre approach and see an independant garage/MOT centre to check/adjust.



"see an independent garage/MOT centre to check/adjust"

yep, it's really easy noddy to do.

done some rough calcs:-

1% is about 60m to where beam ends on ground
1.2%; 50m
1.5%; 40m
2%; 30m

so even a sight out can reduce the range significantly.

Another thing you can do is park facing a wall / garage door. Mark the centre of the dipped light unit on the wall. Back away and put the lights on. The dipped beam is a sharply defined horizontal portion (both lights should project the horizontal line the same distance up the wall) and a sloping line that intersects the horizontal at a point in line with the centre line of the dipped beam light unit. If you back squarely away from the wall, the floors flat etc you can check them reasonably well.

The horizontal and vertical adjustment to each headlight needs to be done together as they interact.

I guess if you measure the height of the light unit (60cm ish) and back away a measured amount with a bit of 'trig' (argh!) you could work out the amount the beam should be below the height mark on the wall. For example 6m away is about 6cm ish.

Anyway, as you said an MoT station!

Ian Walker

Has anyone noticed a "rainbow" effect from their headlights?? I was following a friend's Elise last night (he knew the route!) and he mentioned that every time I hit a bump or road join (A14 around Cambridge) my headlights went psychedelic with red and blue lights appearing in his rear view mirror...! neither of usd had been drinking or smoking anything odd(!) so I guess it has something to do with the projector lenses and refraction of the beam??

I get a rainbow along the top edge of my dipped lights, which you can clearly see when parking in the garage, and it also gets reflected from road signs. The top edge of the dipped beam seems very sharp comparing with previous cars either very dark above or lit up.....this gives a strange effect to cats eyes, they seem to "switch on" as you drive along.


Standard prismatic effect of the projector lens.

Roger Parker

>.this gives a strange effect to cats eyes, they seem to "switch on" as you drive along.

When comming back from the Luton meet, there is a streach of road with LED cats eyes, now they are well cool (esp if you switch your lights off)
Will Munns

This thread was discussed between 14/08/2002 and 23/08/2002

MG MGF Technical index

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