How To:- Fit Standard Foglight Switches/Indication

Well, a couple of months ago I did a little custom modification and put matching, standard style fog light switches into my tubby, illuminated with blue LEDs:



No big deal for a UK car, but for an import, a matching rear foglight switch is a bit of a novelty. Normally you get random switches with red lights built in. The red light acts as the legally required fog light tell tale, which is theoretically also checked on the MOT. My new switches don't have a tell tale... which led to last night's DIYing!

I cut down some dash warning lights from a UK car kindly provided by PeteV6R5 to fit in the blank section of the speedo cluster:



The aim is to put a new bulb into this empty slot here:



The upper rail goes to a pin on the cluster's connector, but the lower rail is 12V IGN. Ideally I wanted to put the bulb between the foglight's +ve and ground, hence I hacked a spare bulb holder to divert one side for a ground feed.



I then cut out the space for the bulb and scraped away the green surface to reveal the copper contact:



The bulb can then be inserted and tied to a ground on the stock boost gauge's circuitry:



Now I hit a problem! My car didn't have a pin present on the connector to tap into. On the same connector should have been the cruise control indicator pin, but as my car didn't have cruise control that wasn't present either. Therefore I ended up soldering a new wire onto the line on the cluster, which could then be connected up the the fog light circuitry:





Finally, the finished result:

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