82 1.5GL Cabby Reversing lights

Reversing lights are very faint with very low illumination, hard to see them! both rear light clusters work ok, all clean connections and bulbs work fine, main engine to body earth strap ok.  Does anyone have any ideas what the problem might be?

Thank You

are the bulds he correct type??

also put a multimeter across the switch in the top of the gearbox and see what the reading is

hth

Yes get a cheap (£10) multimeter and see what the volts are at the bulb. Have you cleaned the earth in left rear corner of boot floor?