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RV8 front indicator lamp - connector terminal corrosion
Brian Moyse (BRG 1714) recently had to replace the offside front indicator lamp assembly on his car after it stopped working. The problem was traced to corrosion of one of the connection pins of the bulb holder where the wiring loom connector is plugged in. (Nov 02)

The lamp unit is simply removed by undoing the two screws on the front lens of the unit and pulling the unit out of the front bumper. The bulb holder is removed from the lamp unit by twisting it anti-clockwise. On inspection, the bulb holder has two fragile looking male connector pins. One appears to be in copper alloy and connects through to the body of the cap of the bulb. The second connector pin appears to be made from plated spring steel and connects through to the terminal on the end of the bulb, this terminal had simply disappeared as a result of corrosion.

The reason for the corrosion is that the indicator lamp assemblies are mounted in the front bumper moulding directly in line with the front road wheels and are therefore blasted in wet weather by whatever mixture of road salt, dirt and water that is around. The connectors on the wiring loom are effectively open and unprotected from the elements, there is no rubber boot fitted, and the corrosive mix will inevitably find its way onto the bulb holder terminals. Once there it will remain damp for some time and do the damage. The female connector terminals in the wiring loom connector block itself do not seem to have suffered, probably because they also are made from copper alloy.

When replacing my lamp unit, I have over-wrapped the connector and bulb holder assembly with a self-amalgamating electrical insulation tape (sometimes

Brian Moyse (BRG 1714) from Surrey

known as Poly Iso Butylene or PIB tape). This is an elastic tape which when stretched over itself will amalgamate into a homogenous water proof mass and firmly grip the object to which it is applied. Hopefully this will delay a reoccurrence of the problem on my new lamp unit.

A spare lamp unit has been ordered from MG Rover, as no doubt near side unit failure will not be far behind. Delivery took about two weeks and the part number is RZKC6428 and the current price is £22.65 plus VAT. My next job is to check out the front fog lamp units which are in a similar location.
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