2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb

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Thu 27 Feb 2014 20:31
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - keymoo

My rear offside lamp was damaged and had to be replaced (the bit on the main body, not on the tailgate). The stop bulb also was out, so I replaced that too. After fitting the new lamp and stop bulb, the stop lamp is on full brightness even when the brake is not depressed. Nearside works fine: i.e. it brightens when brake is pressed.

Any ideas what I've done wrong?

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Thu 27 Feb 2014 22:57
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - elekie&a/c doctor

Wrong bulb or incorrectly fitted.

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Fri 28 Feb 2014 15:21
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - keymoo

I put in a Halfords 380 12V 21/5W. How can it be incorrectly fitted? The bulb light comes on, but at full brightness. Any other ideas?

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Fri 28 Feb 2014 17:13
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - Oli rag

Just swap the bulbs side to side and see if the fault transfers, if it does it's the bulb and if it stays it's probably the lamp contact at fault.

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Fri 28 Feb 2014 17:26
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - elekie&a/c doctor

What happens if you plug in the old lamp unit?

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Sat 1 Mar 2014 07:31
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - Simon
You've put the stop/tail bulb in 180 degrees out. Turn it around and all will be well.
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Sat 1 Mar 2014 12:55
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - Collos25

I was not aware you could put them in the wrong way a chat with one of the mechanics says it is impossible.

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Sat 1 Mar 2014 13:37
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - galileo

I was not aware you could put them in the wrong way a chat with one of the mechanics says it is impossible.

You are correct in that the pins on the bulb are offset to prevent fitting the wrong way round: however, I suppose if enough force is used its possible.

I read an air accident report once where a fuel valve had been fitted the wrong way round; a lug was forged on it to foolproof fitting, but the fitter had cut the lug off so that he could fit it wrong way round.

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Sat 1 Mar 2014 20:16
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - bathtub tom

I've seen stop/tail lamp bulbs fitted the wrong way round, usually by professionals!

I had a car whose amber indicator lenses had faded almost to clear. I fitted amber bulbs instead of clear. The amber bulbs have offset pins, but it was quite a simple job to fit them - with a little force.

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Sun 2 Mar 2014 06:04
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - Simon
In theory the offset stepped pins stop you from putting the bulb in wrong, but in reality what happens is you push the bulb harder down into the contacts and twist the bulb to sit into the wrong lug 180 degrees out and it will sit lower in the bulb holder than it should do. Hence why the tail light is now lighting up the 21w filament and when you press the brakes the 5w filament will light also, but you cannot see it over the brightness of the other one.
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Sun 2 Mar 2014 10:45
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - galileo
In theory the offset stepped pins stop you from putting the bulb in wrong, but in reality what happens is you push the bulb harder down into the contacts and twist the bulb to sit into the wrong lug 180 degrees out and it will sit lower in the bulb holder than it should do.



Its actually because there are two contacts on the bulb and fitting and the wrong ones touch due to being 180 degrees out of the intended position.
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Thu 6 Mar 2014 18:08
2007 Ford S-Max - Problem Replaced offside rear lamp and stop bulb - keymoo

Sorry it's taken a while to report back. I bought two new bulbs and fitted them and all is well. It's quite possible that I fitted the bulb the wrong way round - didn't know that the orientation mattered. Can't be bothered to pull the unit out again and test it but all is well.

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