4.2 Front Foglamps - Performance

[Tech01]

Just a quick write-up of something I did a couple of years ago...

The performance of the "rectangular" front foglamps on the 4.2 is appalling, and you'd never think there was reasonable-spec 51-watt lamp lurking in there. Light output seems more like half that, and the light just goes everywhere, and nowhere useful. (Eventually the rectangular lamps were replaced by larger circular ones, and the indicators shifted to the headlamp units.)

I read some time ago of a couple of folk who had identified the problem, and sorted it. It simply involved removing the internal metal lamp 'baffle' inside the foglamp! There was a word of caution about doing this in general to small light units, because the baffle is intended to protect the front plastic cover from direct heat and UV discolouration. But, the 4.2's front foglamps have glass fronts (no problem with UV) and relatively low-power 51-watt lamps.

I decided to give it a try. First, remove the fog-lamp (indicator lamp comes out first, allowing fog-lamp removal). You will see that the lamp consists of two halves (reflector and front lens) which are firmly bonded together. Do not try to separate them! Remove the lamp, and you can peer into the lamp unit, and see the thin chromed metal pressing which covers the front of the lamp. This metal pressing needs to be removed.

I did it by snipping away at it with some side-cutters, and then using some point-nosed pliers to squash it and twist it (maybe in several small bits) and remove it from the lamp. Try not to scratch or damage the silvered reflector, which seemed to survive the operation without a problem. (One guy on Rav4world referred to using a Dremel for all this, but I didn't have a suitable one.) Extraction might take you 20 minutes per lamp: take it slowly.

That's it. Refit the bulb, and refit the two lamp fittings.

Result? Light output seems to quadruple, and places a really useful spread of light right across the front of the vehicle, on the ground and to the sides - just what you'd expect front fogs to do! No noticeable increase in dazzle, and no problems with the vehicle test. Front lenses seem only mildly warm, even after long periods of use and when stationary.

I'm sure several other folk must have done this. Sorry if this has been documented here before.

Chris

r4.bmp

[Joylove]

Thanks, nice Sunday afternoon project. :)